Authors: Weijian Zhang Zaiwang Zhang Zenghui Diao
In recent years, soil contamination by heavy metals and organic pollutants has become a serious environmental problem. Biochar is a highly carbonaceous, water-insoluble porous material made from biomass feedstock through a thermochemical conversion process, and it has been widely used in the remediation of various soil pollutants. However, previous reviews on the modification of biochar and the remediation reaction mechanism of heavy metals and organic pollutants by biochar in soil were still not sufficiently comprehensive. Based on the current research status of the remediation of heavy metals and organic pollutants by biochar in soil, this review systematically summarized biomass feedstock types, pyrolysis methods and their applicable scenarios, as well as the modification strategies of biochar, including pore structure modification, surface functional group modification, surface charge modification, and magnetic modification. It also comparatively discussed the adsorption of heavy metals by biochar mainly through electrostatic attraction, ion exchange, complexation/precipitation, cation−π interaction, and redox transformation, while the adsorption of organic pollutants via π−π/EDA interactions, electrostatic attraction, hydrogen bonding, hydrophobic partitioning, and pore filling were outlined. The review also discussed competitive effects among pollutants during biochar adsorption under co-contamination scenarios, as well as the synergistic interactions between biochar and soil microorganisms or plants. In addition, the review addressed recent progress in field-scale applications of biochar, as well as the current state of research on aging effects, ecological risks, and economic feasibility. Finally, it identifies key research directions that warrant further attention. This review highlighted the mechanistic differences between heavy metal stabilization and organic pollutant removal in soil by biochar, and provided mechanistic insight and guidance for biochar-based soil remediation.
]]>Authors: Rahul R. Bhosale
Monoethanolamine (MEA) remains the predominant solvent for carbon dioxide (CO2) capture due to its rapid reaction kinetics, substantial absorption capacity, and demonstrated industrial effectiveness. Despite its established status, MEA-based systems are undergoing continuous development to lower energy requirements, enhance solvent stability, and expand operational adaptability. This review provides a critical assessment of recent progress in MEA-based CO2 capture, encompassing molecular-level understanding, advancements in reactor and process design, solvent modification strategies, and system-wide optimization. Recent theoretical and experimental research has improved the understanding of CO2 absorption mechanisms in MEA, highlighting the effects of reaction-product buildup, interfacial phenomena, and free amine availability on mass-transfer efficiency. Reboiler duty and comparable work have significantly decreased as a result of advances in process intensification, improved regeneration systems, and energy-integration techniques. New hybrid strategies that partially decouple capture from thermal regeneration, such as combined absorption–mineralization pathways, show promise for long-term CO2 sequestration. To address regeneration energy, corrosion, degradation, and cyclic stability, this review examines advances in MEA-based solvents, including aqueous blends, non-aqueous and biphasic systems, ionic liquids, and deep eutectic solvent hybrids. It also critically assesses the trade-offs of developments in intensified contactors, surfactants, nanomaterials, and catalysts. The growing role of digital optimization, machine learning, and computational modeling in MEA process design and control is highlighted. Overall, this analysis underscores MEA’s continued importance as a versatile platform for next-generation carbon capture, utilization, and storage.
]]>Authors: Ziting Zhang Juan Du
Carbon quantum dots (CQDs) have attracted considerable attention as versatile fluorescent nanomaterials in the domains of food safety and preservation, primarily due to their tunable photoluminescence, high aqueous dispersibility, and favorable biocompatibility. Although numerous reviews have documented the synthesis and extensive applications of CQDs, a focused critical assessment specifically addressing how rational surface functionalization and heteroatom doping impact their performance within complex food matrices remains absent. This review provides a targeted analysis of the interplay between the functional design of CQDs, including both surface group engineering and elemental doping, and their practical efficacy in food-related applications. Initially, a concise overview of the fundamental aspects of CQDs relevant to their functionality is presented, emphasizing the origin and role of surface chemical groups and pivotal photophysical sensing mechanisms. Subsequently, the core of the review critically evaluates recent advancements (particularly those from 2022 onward) in the use of functionalized CQDs for detecting food contaminants (such as heavy metals, pesticide residues, antibiotic residues, pathogens, and additives) and in food preservation techniques, including active packaging, antioxidative and antimicrobial coatings, and photodynamic inactivation. Through a systematic comparison of analytical figures of merit and the effects of various matrices across different design approaches, we delineate both the established capabilities and the current limitations of CQD-based technologies in realistic food systems. The review concludes by identifying ongoing challenges, specifically, batch-to-batch consistency, the long-term safety profile of CQDs in food-contact applications, and the translation gap from laboratory innovation to industrial practice, and outlines prospective research directions. The overarching aim of this work is to provide a structured framework for understanding how deliberate functional design can lead to improved performance, thereby guiding the rational development of next-generation CQD-based materials for ensuring food quality and public health.
]]>Authors: Laurique N. Hughes Natasha Mastalka-Tatro Kevin Tvrdy
The chirality-specific study of single-walled carbon nanotubes (SWCNTs) necessitates their solution-phase processing with tip-horn sonication in the presence of a stabilizing surfactant such as sodium dodecyl sulfate (SDS), a process that has been shown to introduce sonochemical side-products such as dodecanol, dodecanal, and dodecene. This work employs single-column interactions within the overloading regime to quantitatively assess the impacts of dodecanol, dodecanal, and dodecene on the ability to purify SWCNTs using Sephacryl S-200 hydrogel. Increasing concentrations of each additive caused a corresponding decrease in the number of SWCNTs adsorbed to the gel, with a 50% reduction in SWCNT uptake realized at 0.75–1.00 mM for all three additives. Per-chirality adsorption selectivity was unaffected by relatively low additive concentration, but it was significantly hindered nearer the solubility limit of each additive. Elution efficiency from each gel was independent of additives, additive concentration, and SWCNT chirality. Mechanistically, these findings suggest the integration of each additive within the micelle structure of SDS. While the concentration of each additive introduced during tip-horn sonication is insufficient to impact gel-based SWCNT purification, the presence of dodecanol impurities within as-purchased SDS have the potential to significantly impact the purification outcome, suggesting that future studies of gel-based SWCNT purification should be carried out with SDS purified by recrystallization.
]]>Authors: Samah Daffalla
A mesostructured activated carbon (PL–AAC) was engineered from palm leaf biomass via a specific chemical activation protocol and systematically evaluated as a bifunctional adsorbent–catalyst for the advanced oxidative removal of methyl orange (MO) from aqueous media. Physicochemical characterization confirmed the successful transformation of the lignocellulosic precursor into a hierarchically porous carbon framework, exhibiting enhanced surface area (2 → 56 m2/g), increased pore volume (0.0106 → 0.0227 cm3/g), and a dominant mesopore distribution (~3–5 nm). FTIR analysis revealed the presence of oxygen-containing functional groups (hydroxyl, carbonyl, and carboxyl), while SEM images demonstrated the formation of interconnected pore channels. Nitrogen adsorption–desorption isotherms showed Type IV behavior with H4 hysteresis, confirming the presence of narrow slit-shaped mesopores and micropores. This study introduces the novel application of palm leaf-derived activated carbon as a dual-function material that integrates adsorption and catalytic oxidation within a single system. Under acidic conditions (pH 2–3), PL–AAC in the presence of H2O2 achieved near-complete MO removal (≈98–100%), driven by the synergistic interaction between adsorption and in situ generation of reactive hydroxyl radicals. Kinetic analysis revealed that the degradation follows a pseudo-second-order model (R2 = 0.916), indicating that surface-mediated interactions govern the process. Furthermore, PL–AAC maintained high catalytic efficiency over four regeneration cycles with negligible performance loss, demonstrating excellent stability and reusability. These findings highlight the effective valorization of palm leaf waste into a sustainable, low-cost, and high-performance material for advanced wastewater treatment applications.
]]>Authors: Sergey Osipov Vadim Yakovlev Polina Golosova Dmitry Pisarev Andrey Rogalev
Direct-fired supercritical CO2 cycles are considered a promising way to reduce CO2 emissions in the energy sector. One of the key elements of such cycles is a combustor, in which natural gas is burned at supercritical pressures up to 300 atm in an O2/CO2 environment. Understanding the chemical combustion kinetics of C1–C4 alkanes, the main components of natural gas, in a supercritical CO2-diluted medium is important for designing such combustors. This article provides an overview of studies on the chemical kinetics of C1–C4 alkanes combustion in CO2 at ultra-high pressures. It has been established that with increasing pressure, regardless of the diluent, CH3O2 and HO2 chemistries start to significantly influence the combustion of alkanes, but at the moment this influence is not sufficiently understood. Influence of CO2 dilution on kinetics is mainly thermal, but the chemical effect is also significant. At the same time, the direct chemical effect of CO2 is more important for the laminar burning velocity, while the indirect third-body effect is more important for the ignition delay time. However, the available literature lacks experimental measurements of the laminar burning velocity in a CO2 environment at pressures above 70 atm, which limits the current understanding of chemical kinetics at supercritical pressures.
]]>Authors: Bharti Gaur Jyoti Mittal Hadi Hassan Alok Mittal Richard Thornton Baker
Metanil Yellow (MY), a highly toxic azo dye used in food products, was removed from aqueous solution using a metal- and halide-free ordered mesoporous carbon (OMC) adsorbent. MY exhibited a strong affinity towards OMC in batch as well as column operations, and OMC performed much better than previously reported adsorbents. The pH, dye concentration, adsorbent dosage, and contact time were optimised, and detailed adsorption experiments were performed under these conditions. Several isotherm models were fitted to the adsorption data, showing that the Langmuir and the Freundlich adsorption models were followed. Adsorption was spontaneous and endothermic at all measurement temperatures. On the basis of pH studies, enthalpy data, and adsorption isotherm analysis, adsorption was determined to be by physisorption. In kinetics studies, the adsorption process was found to be pseudo-second order with interparticle diffusion as the rate-limiting step. Column experiments using a fixed bed of OMC resulted in almost 100% column efficiency and a fractional column capacity of 0.999. During adsorption/desorption cycles of the exhausted column, 99.71% of the dye was recovered after the first cycle and 97.66% after the eleventh. These findings indicate that OMC is a promising and efficient material for the adsorptive removal of toxic MY dye.
]]>Authors: Gimhani Danushika Pei Lay Yap Siavash Aghili Gurleen Singh Sandhu Dusan Losic
Graphene-related materials (GRMs) possess exceptional electrical, mechanical, thermal, and surface properties, offering significant potential across broad sectors and applications in electronics, energy storage, composites, and environmental technologies. Despite extensive investment in academic research and translation, large-scale industrial adoption of GRMs remains slower than projected. This review systematically analyzes the global graphene manufacturing landscape using available data from 100 commercial producers, with a focused evaluation of manufacturing technology, types and forms of produced GRMs, raw material sources, product forms, industrial quality control and characterization practices. Graphite-based production routes, particularly graphene oxide (GO) and reduced graphene oxide (rGO), dominate in the market due to their scalability and cost advantages. However, substantial inconsistencies in the quality of produced GRMs, characterization and standardization depth, analytical evidence, and technical data sheets (TDSs) remain widespread. A SWOT (strengths, weaknesses, opportunities and threats) analysis of emerging graphene in the industry highlights technological maturity and expanding market demand but reveals critical weaknesses and challenges in quality, standardization and cost–performance alignment. Overall, quality of manufactured materials, quality control transparency, and standardization rather than material manufacturing limitations emerge as the primary barriers to the widespread commercial realization of graphene.
]]>Authors: Sung Hee Joo
Microplastics (MPs) are increasingly recognized as persistent, carbon-based contaminants in biosolids produced during wastewater treatment. As biosolids are widely applied to land or disposed of via landfilling and incineration, the incorporation of microplastic-derived carbon into managed and natural ecosystems raises important questions regarding carbon cycling, organic carbon stability, and long-term environmental implications. This review synthesizes current knowledge on the occurrence, characteristics, and fate of microplastics in biosolids, with particular emphasis on their interactions with native organic matter and their influence on carbon-related processes. This work critically assesses how MPs in biosolids influence carbon dynamics, including their role as a persistent carbon pool, interactions with soil organic matter, effects on microbial activity and decomposition, and implications for carbon sequestration and turnover after land application. The review also considers indirect consequences for food systems and human exposure through carbon-associated pathways. Significant knowledge gaps remain regarding the quantification of microplastic-associated carbon stocks and fluxes, transformation processes during biosolid treatment and soil incorporation, and the long-term persistence of this carbon fraction. Methodological challenges in measuring and reporting MPC are briefly highlighted, alongside their implications for understanding MPs as an emerging component of the terrestrial carbon cycle and for sustainable biosolid management.
]]>Authors: Henri Perez Claire Dazon Pierre Lonchambon Suzy Surblé Emeline Charon Mathieu Frégnaux Arnaud Etcheberry Charles Rivron Olivier Sublemontier
We report the synthesis of Fe/N/C ORR electrocatalysts by an original collinear CO2 laser pyrolysis of liquid aerosol droplets in various configurations and compared them to a catalyst synthesized in the classical perpendicular one. While the precursors were always injected at the bottom side of the reactor, two collinear configurations of the laser entry into the reactor are considered: by the Top Side (T.S.) or by the Bottom Side (B.S.). The two corresponding catalysts sets show significant different ORR performances. An in-depth XPS analysis and fitting of the N1s spectra allowed for drawing the ORR performance as a function of FeNx sites components. An original approach considering the energy delivered to a quantity of precursors in J.g−1, linked to the flame temperature feature, evidenced very different conditions for perpendicular CO2 laser pyrolysis and each of the two collinear configurations. This mass-weighted energy delivered in the classical perpendicular configuration is too low to allow for the formation of FeNx sites and the resulting ORR performance is extremely poor, suggesting a marginal role of nitrogen species without interaction with iron atoms. In contrast, the delivered mass-weighted energies are sufficient in both collinear configurations to produce FeNx sites. The ORR performance for catalysts produced in these both configurations is positively correlated with the amount of energy deposited on the precursors. The ORR performance in the T.S. laser configuration is positively correlated to the amount of FeNx sites. The best performing catalysts obtained in the B.S. configuration show an opposite variation. These trends, and the ORR performance degradation of B.S. catalysts under prolonged chronoamperometry are discussed in light of the effect of temperature on the formation of the various kind of FeNx sites. A tentative explanation is given, considering that N1s XPS fitting with a single FeNx component may hinder the fact that Pyridinic sites components may contain a part of FeNx sites, as suggested by theoretical calculation from the literature. The best catalysts obtained in this work by collinear configuration show similar performances to those obtained by double stage perpendicular pyrolysis previously reported with an ORR onset potential of ~860 mV.
]]>Authors: Magdalena Sobiesiak Monika Parcheta Rosa Busquets
Activated carbons are usually prepared from natural precursors (e.g., fruit stones or nutshells) by carbonization and activation processes carried out at 400–1000 °C. They exhibit well-developed porosity, and chemical activation introduces hydrophilic functional groups on their surface, providing excellent sorption properties. However, the high temperatures required during thermal treatment increase production costs. In this work, cost-reducing methods for preparing carbon sorbents are proposed. Carbonization of H3PO4 activated waste pistachio nutshells was performed using classical pyrolysis (500 or 550 °C, 30 min, N2 atmosphere) and microwave treatment (power 1000 W, 20 min). The properties of the synthesized carbons were characterized using thermogravimetry and spectroscopic techniques including infrared (ATR), Raman, photoelectron (XPS) spectroscopies, and scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM-EDS). Porous structure parameters were determined using nitrogen adsorption experiments. The efficiency of Pb2+ removal from spiked ultrapure, tap and river water was evaluated by batch sorption experiments and inductively coupled plasma–mass spectrometry. The most porous carbons were those prepared at 500 and 550 °C, with specific surface areas of 910 and 256 m2/g, respectively. Surface phosphates increased the Pb2+ sorption efficiency to 99% from ultrapure water, at an initial concentration of 300 µg Pb2+/L. The material obtained with the microwave method was not fully carbonized and remained nonporous, but it also exhibited 99% Pb2+ uptake from ultrapure water due to the presence of oxygen-containing surface groups. The Pb2+ removal from spiked tap and river water reached up to 84% and 94%, respectively, at the spiking level of 300 µg Pb2+/L.
]]>Authors: Kiara Cruz Simeng Li
Microplastic pollution has emerged as a major environmental concern due to its persistence, widespread distribution and potential risks to ecosystems and human health. Among the various types of microplastics, fibrous microplastics (FMPs) account for 60% to 90% of all detected microplastic particles in surface waters, primarily originating from synthetic textile production, laundering, and wastewater discharge. Their elongated morphology, high aspect ratio, and complex surface chemistry differentiate them significantly from microplastic fragments or beads, creating unique challenges for effective removal in water treatment systems. In recent years, engineered biochar has attracted increasing attention as a promising and sustainable material for microplastic removal due to tunable pore structure, surface chemistry, and adsorption capacity. However, existing reviews largely discuss microplastic removal in general terms, with limited attention to the distinctive properties of textile FMPs and their implications for biochar design and performance. This review provides a comprehensive and focused analysis of the functional characteristics of biochar that enable the effective removal of textile FMPs in water systems. First, the environmental significance and physicochemical characteristics of textile-derived FMPs are summarized. Next, the major mechanisms governing biochar–microplastic interactions, including physical interception, adsorption, and aggregation processes, are discussed. The review then examines key functional characteristics of engineered biochar, such as pore structure, surface functional groups, hydrophobicity, and composite modifications, that enhance the sequestration of FMPs. Finally, current technological challenges, research gaps, and future directions for developing scalable biochar-based solutions for textile microplastic mitigation are discussed. By linking the unique properties of textile FMPs with the functional design of biochar, this review provides a framework to guide the development of more effective and sustainable treatment strategies for reducing microplastic contamination in aquatic environments.
]]>Authors: Nikolay Viktorovich Baranovskiy Viktoriya Andreevna Vyatkina
The object of the study is a single heated carbonaceous particle of relatively small size, 0.003 to 0.01 m. Main hypothesis: The formation of soot particles and black carbon particles is caused by the thermochemical destruction of dry organic matter of forest fuel and the mechanical fragmentation of coke residue. The aim of the study is to conduct numerical simulations of heat and mass transfer in a single heated carbonaceous particle, taking into account the soot formation process and assessing its fragmentation with regard to heat exchange with the external environment in a 2D setting. As part of this study, a new model of heat and mass transfer in a pyrolyzed carbonaceous particle was developed, taking into account its step-by-step fragmentation (fragmentation tree model with four secondary particle formations from the initial particle). The calculations resulted in the distributions of temperature and volume fractions of phases in the carbonaceous particle across various scenarios. Scenarios of surface fires (initial temperatures of 900 K and 1000 K), crown fires (1100 K), and a firestorm (1200 K) for typical vegetation (pine, spruce, birch) are considered. Cubic carbonaceous particles are considered in the approximation of a 2D mathematical model. To describe heat and mass transfer in the structure of the carbonaceous particle, a differential equation of thermal conductivity with corresponding initial and boundary conditions of the third type is used, taking into account the gross reaction in the kinetic scheme of pyrolysis and soot formation. Differential analogues of partial differential equations are solved using the finite difference method of second-order approximation. Options for using the developed mathematical model and probabilistic fragmentation criterion for assessing aerosol emissions are proposed. Recommendations: The suggested mathematical model must be incorporated with mathematical models of forest fire plume and aerosol transport in the upper layers of the atmosphere. Moreover, probabilistic criteria for health assessment must be developed for the practical use of the suggested mathematical model.
]]>Authors: Mohammed Mohammed Katelyn Hamilton Mia Dial Venkateswara R. Kode
Water vapor sorption in porous activated carbons (PACs) is governed by a complex interplay of pore architecture and surface functionality and often exhibits pronounced adsorption–desorption hysteresis. In this work, chestnut-shell-derived carbons were synthesized via a two-step thermal route—pyrolysis at 550 °C for 120 min followed by KOH activation at either 600 °C or 800 °C for 240 min—and evaluated using a dynamic vapor sorption analyzer to quantify water uptake, hysteresis, and temperature-dependent energetics. Both materials exhibit sigmoidal Type V isotherms, characteristic of cooperative water clustering on hydrophobic carbon surfaces with localized polar sites. At 25 °C, The PAC sample prepared at 800 °C shows a sharper uptake transition and higher total capacity (~0.45 g/g at 90% RH), compared to the broader, more gradual isotherm of the 600 °C sample (~0.17 g/g). Temperature-dependent isotherms collected between 25 °C and 45 °C were fit using the Dubinin–Serpinsky (DS-4) model, yielding good agreement (R2 ≈ 0.997) and enabling mechanistic interpretation of primary site adsorption and cooperative cluster growth. Clausius–Clapeyron analysis of ln P versus 1/T at fixed loadings yielded isosteric heats of adsorption (ΔH) decreasing from approximately 45.4 kJ mol−1 at low uptake (0.02 g g−1) to ~43.8 kJ mol−1 at intermediate loading, followed by a slight increase to ~44.2 kJ mol−1 at higher coverage (0.35 g g−1). This trend reflects the transition from strong adsorption at high-energy surface sites to cooperative water clustering and confinement effects within the pore network. These findings highlight the role of activation temperature in modulating sorption mechanisms and energetics, offering practical guidance for tuning biomass-derived carbons for atmospheric water harvesting applications.
]]>Authors: Siddharth Atal Sonam Sharma Amit Kumar Gomey Syed Saim Ali Rakesh Kumar Deepak Dwivedi Bhupendra Pratap Singh
Carbon dioxide emissions from fossil fuel burning remains a severe environmental challenge that needs to be addressed. Deep eutectic solvents (DESs) have emerged as promising alternatives to conventional alkanolamines for CO2 capture applications due to their lower volatility and reduced corrosion potential. In this work, two tetrabutylammonium bromide (TBAB)-based systems were synthesized using different hydrogen bond donors: 2-amino-2-methyl-1-propanol (AMP) at a 1:1 molar ratio and p-toluenesulfonic acid (PTSA) at a 1:2 molar ratio. FTIR spectroscopic analysis confirmed that TBAB-AMP (1:1) forms a true DES through hydrogen bonding interactions, whereas TBAB-PTSA (1:2) undergoes proton transfer to form an ionic salt. CO2 solubility measurements were conducted using the pressure drop method up to 15 bar at 30 °C. The TBAB-AMP system exhibited a CO2 uptake of 0.194 mol CO2/mol DES at 14.7 bar, approximately 2.5-fold higher than the TBAB-PTSA system, which achieved 0.079 mol/mol at 14.5 bar. Critical and thermophysical properties were estimated using the modified Lydersen–Joback–Reid, Lee–Kesler, and Haghbakhsh group-contribution methods. Viscosity measurements conducted from 30 to 50 °C revealed that TBAB-AMP exhibited significantly lower viscosity, ranging from 163 to 46 mPa·s, compared to TBAB-PTSA, which showed viscosity values between 536 and 155 mPa·s. The superior CO2 capture performance of the amine-functionalized DES was attributed to favorable hydrogen-bonding interactions, lower viscosity, which enabled better mass transfer, and enhanced chemical affinity toward CO2 through carbamate formation.
]]>Authors: Iriana Garcia Guerra Deissy. J. Feria Gustavo M. A. Alves Jandro L. Abot Inés Pereyra Marcelo N. P. Carreño
Carbon nanotube yarns (CNTYs) have received more consideration recently due to their excellent specific mechanical, electrical and thermal properties, making them promising materials for different applications. Until now, the axial properties of the yarn have been thoroughly investigated; however, the transverse or radial properties, orthogonal to the fiber axis, remain relatively unknown due to the challenges associated with their measurement. In this study, the transverse or radial response of the CNTY including its elastic modulus was determined using Atomic Force Microscopy (AFM) and Raman Spectroscopy. Determining transverse properties in fibrous materials presents challenges owing to their geometry, inherent anisotropy, whereby mechanical characteristics exhibit directional disparities; i.e., the properties in the transverse direction may be several orders of magnitude smaller than those in the axial direction. To overcome these difficulties, AFM was utilized to perform nanoindentation experiments, where a tipless flexible cantilever probe was used to apply a controlled force to the CNTY surface. The resulting indentation depth was then analyzed to determine the transversal elastic modulus. Preliminary findings indicate that the transverse elastic modulus of the CNTYs ranges from 10–54 kPa for strain levels below 3%. Complementary Raman spectroscopy provided insight into the bulk-scale mechanical behavior of CNTYs. Incremental compressive loading between microscope slides induced nonlinear upshifts in the 2D Raman band (from ~2686.6 to 2691.4 cm−1), indicating nanoscale tube realignment, inter-tube densification, and compaction. From lateral diameter measurements under load, a stress–strain curve was constructed, revealing three distinct regimes: one with an initial elastic modulus of 3.12 MPa (0.3–11.2% strain), another one with an elastic modulus increasing to 8.46 MPa (11.2–14.4%), and finally one with an elastic modulus peaking at 16.86 MPa beyond 14.4% strain. Together, these methods delineate the hierarchical and anisotropic nature of CNTYs, validating the importance of multiscale mechanical characterization for their deployment in piezoresistive sensors and multifunctional composites. This study establishes a robust framework for quantifying the transverse mechanical response of CNTYs.
]]>Authors: Ionuț Mititelu Viorel Goanță Paul Doru Bârsănescu Ciprian Ionuț Morăraș
Most components fail under complex states of stress and for this reason the study of materials failure under these conditions is an important topic. The article presents the experimental study of the failure of a CFRP material, with a 0/90° cross-ply configuration, subjected to both simple loading conditions (tension, compression, and shear) and combined loading (tension–shear), using a modified Arcan testing method. The Arcan device and specimen geometry were redesigned to reduce experimental errors and the dispersion of results. It was found that there are significant differences between the strength values obtained for simple loads performed by the standardized methods and by the Arcan method, respectively. For this reason, it is recommended to use the Arcan method only for mixed loading modes. Specimens with steel tabs were used to reduce both hole ovality during testing and the number of clamping screws to only four. It was found that the experimental results under complex stress states are well described by the Tsai–Hill failure criterion and the failure envelope for the material studied was plotted. Recommendations are provided regarding the appropriate use of the Arcan method in order to obtain precise results for CFRP composites under multiaxial loading.
]]>Authors: Tamara Lazarević-Pašti Vedran Milanković Nevena Radivojević Tamara Terzić
Organophosphate pesticides (OPs) are widespread contaminants in agricultural and aquatic environments. Growing evidence indicates that even low-level, chronic exposure to OPs is associated with neurotoxic effects and long-term neurological risks. Over the past decade, substantial progress has been made in developing porous carbon materials capable of efficiently removing OPs from water, food systems, and other environmental matrices. However, adsorption studies have largely focused on equilibrium performance metrics rather than on conditions relevant to real exposure scenarios. This review introduces an exposure-oriented perspective for evaluating porous carbon materials for OP mitigation by linking adsorption science with exposure-driven neurotoxicity considerations. By analysing recent studies on OP adsorption, we demonstrate that equilibrium adsorption capacity alone is often a poor predictor of real-world exposure mitigation. Instead, adsorption kinetics at low concentrations, pore accessibility, and surface chemical heterogeneity emerge as key factors governing sustained OP sequestration. The review further highlights how hierarchical pore architectures and balanced surface functionalization can enhance adsorption efficiency under environmentally realistic conditions. By integrating environmental carbon research with exposure-relevant considerations, this work outlines design principles for carbon adsorbents to reduce long-term OP exposure and associated neurological risks.
]]>Authors: Azam Ali Muhammad Zaman Khan
The rapid growth of synthetic textile production has intensified the release of micro- and nanoplastics (MPs/NPs) into aquatic environments, primarily through industrial effluents and domestic laundering. Textile-derived microplastics, especially polyester fibers and polymeric coating fragments, constitute a significant fraction of plastic contamination in wastewater systems. Although wastewater treatment plants (WWTPs) can remove a large proportion of MPs, substantial quantities accumulate in sewage sludge, raising concerns about long-term environmental persistence and secondary release pathways. This review critically examines the sources, classification, and release mechanisms of textile-based micro- and nanoplastics, including fibrous debris and coating-derived fragments. Then it focuses on current identification and removal technologies, such as sedimentation, coagulation/flocculation, electrocoagulation, flotation, membrane filtration, adsorption, and biodegradation, and on the emerging strategy of converting recovered microplastics into value-added porous carbon materials via hydrothermal treatment and pyrolysis. Carbonized microplastics exhibit high surface area and adsorption capacity for dyes, heavy metals, and organic pollutants, offering a circular approach that simultaneously mitigates plastic pollution and enhances wastewater treatment efficiency. By integrating source control, optimized removal technologies, and carbonization-based valorization, this review proposes a dual-benefit framework that transforms textile-derived microplastic waste from an environmental liability into a functional resource for sustainable water purification.
]]>Authors: Sofia Fykari George Z. Kyzas Athanasia K. Tolkou
In this work, sustainable aluminum-modified orange peels functionalized with graphene oxide (OP-Al-GO) were synthesized and evaluated for the removal of Methylene Violet (MV) and Reactive Red 120 (RR120) from aqueous solutions. Adsorption performance was systematically investigated in single-dye systems, binary dye mixtures, and real textile wastewater samples, and compared with that of orange peels (OP), orange peel–aluminum composite (OP-Al), and graphene oxide (GO). pHpzc analysis clarified the surface charge of the adsorbent, while SEM and FTIR showed that the incorporation of aluminum and GO increased roughness and functional groups appearance, enhancing dye adsorption and confirming successful interactions. The OP-Al-GO composites exhibited improved removal efficiency for both dyes (64.8% for RR120 and 96.2% for MV) at pH 3.0. The presence of aluminum improved structural stability and surface charge regulation, while graphene oxide contributed to multiple adsorption mechanisms, including electrostatic attraction and π–π interactions. The adsorption kinetics were found to follow a pseudo-second-order (PSO) kinetic model for RR120 and an intraparticle-diffusion model (IPD) for MV, while isotherm analysis revealed a Langmuir behavior for MV and a Freundlich behavior for RR120. Langmuir maximum adsorption capacities were 298.7 and 10.8 mg/g for MV and RR120, respectively. High removal efficiency was maintained in binary dye mixtures, with OP-Al-GO achieving 96.9% removal of MV and 85.7% of RR120. Furthermore, the proposed adsorbent was tested on real wastewater samples, and the results highlight that the proposed adsorbents are promising, low-cost, and environmentally sustainable for textile wastewater treatment.
]]>Authors: Maria Apostolopoulou Nikos Kavousanos Feidias Bairamis Konstantinos Brintakis Athanasia Kostopoulou Emmanuel Stratakis Emmanuel Spanakis Ricardo Santamaría Ramirez Dimitris Kalderis Dimitra Vernardou
Conventional carbon-based electrodes like graphene are limited by costly, energy-intensive synthesis that rely on non-renewable precursors, challenging their scalability. While biomass-derived carbons (biochar) are a promising green alternative, achieving state-of-the-art performance typically requires chemical activation. Developing high-performance biochar through simple, scalable, and green pathways therefore remains a key challenge. In this work, we present a comprehensive physicochemical characterization of activation-free biochar derived from walnut, carob, rice husk and coffee via simple pyrolysis. Surface area, porosity and structural disorder were systematically analyzed to identify the key parameters governing ion interaction and charge storage. The results reveal a strong dependence of biochar properties on biomass type, with pronounced differences in accessible porosity and defect density. Among the materials studied, walnut-derived biochar combined a high specific surface area (1146 m2/g) with a high degree of structural disorder, highlighting the critical role of defects in enhancing ion adsorption and charge-transfer processes. Electrochemical measurements illustrated the functional implications of these intrinsic characteristics. Overall, this work demonstrates that carefully selected, unprocessed biomass can serve as a direct, low-cost source of functional carbon electrodes, providing insight into the parameters that dictate their electrochemical behavior and enable broader functional potential.
]]>Authors: Gathot Heri Sudibyo Laurencius Nugroho Yanuar Haryanto Hsuan-Teh Hu Fu-Pei Hsiao Paulus Setyo Nugroho Nanang Gunawan Wariyatno Banu Ardi Hidayat Dahlan Titis Kuncoro
The strengthening of reinforced concrete (RC) beams requires repair systems that can enhance strength, stiffness, and energy dissipation without significantly increasing self-weight or compromising durability. This study explores the structural response of RC beams strengthened using an integrated shear–flexure system combining near-surface-mounted carbon fiber-reinforced polymer (NSM-CFRP) ropes and steel-reinforced geopolymer overlays in the compression zone. Monotonic three-point bending tests were performed on two RC beam specimens, one unstrengthened control and one strengthened beam, to obtain preliminary observations of load–deflection behavior, stiffness, ductility, and energy absorption. The strengthened specimen exhibited increases in ultimate load (28.6%), stiffness (13.6%), and energy absorption (7.65%) relative to the control beam, suggesting the potential for effective composite action between the CFRP ropes and geopolymer material. A three-dimensional nonlinear finite element model was developed using ATENA to support interpretation of the experimental response, incorporating detailed constitutive models for concrete, steel reinforcement, and CFRP ropes. The numerical predictions showed reasonable agreement with the experimental results. Within the limitations of the test matrix, the results indicate that the proposed dual strengthening system may offer a viable and sustainable approach for enhancing the shear–flexural performance of RC beams.
]]>Authors: Elena F. Sheka
This review presents the covalent chemistry of carbon from the point of the spin-radical concept of electron interaction in the framework of the unrestricted molecular orbitals (UHF MO) theory. Using the language of valence bond trimodality, the regions of classical spinless spin-symmetric covalence and its spin-dependent asymmetric counterpart are defined. Carbon is the only element exhibiting spin covalent chemistry. Classical covalent chemistry of carbon of molecular substances whose valence bond structure includes segregate or chained single sp3C−C bonds meet its spin counterpart only at these bonds breaking. Substances with double sp2C=C and triple sp1C≡C bonds are the subject of spin covalent chemistry of carbon. The mathematical apparatus of the UHF MO allows forming algorithms controlling the chemical modification of carbon substances, polymerization processes, and catalysis involving them, making it possible to supplement the empirical spin covalent chemistry of carbon with its virtual analog.
]]>Authors: Qi Qiang Kezhi Li Tianzhan Shen Haibo Ouyang
The pantograph slider is a key friction component in high-speed train systems, and its performance directly affects the safety and efficiency of operation. In this study, Cf/C/CuNi composites with carbon fiber contents of 1 wt.%, 3 wt.%, 5 wt.%, and 7 wt.% were prepared by a solvothermal method combined with spark plasma sintering (SPS). The influence of carbon fiber content on the mechanical and friction properties of the composites was systematically studied. The results show that the flexural strength of the composites increases from 20.20 MPa to 38.45 MPa with an increase in the carbon fiber content. However, excessive carbon fiber content can lead to fiber agglomeration and interface defects, thereby reducing the friction stability and increasing the wear rate from 0.64 g/m3 to 1.60 g/m3. A carbon fiber content of 1 wt.% helps to form a continuous lubricating film, resulting in a low and stable friction coefficient. This study provides valuable insights for the design and optimization of high-performance pantograph slider materials for high-speed railway applications.
]]>Authors: Takashi Uchino Yanjun Heng Chao Tang Akira Satou Hirokazu Fukidome Taiichi Otsuji
Advanced solar energy-harvesting devices, such as optical rectennas, typically use metal–insulator–metal diodes because of the ultrafast response of these diodes at high frequencies. However, the diode performance is limited by weak current–voltage (I–V) asymmetry and optical losses in metallic electrodes. Graphene offers a promising alternative electrode material owing to its high carrier mobility, broadband optical transparency, and compatibility with nanoscale device architectures. Nevertheless, graphene-based optical rectennas face challenges associated with insufficient diode nonlinearity. In this study, we developed a vertically stacked graphene–double-insulator–graphene (GI2G) tunnel diode. Devices with various junction sizes were fabricated to investigate size-dependent rectifying behavior. A reduced graphene overlap area was defined by electron-beam lithography to introduce asymmetry and increase nonlinear conduction. An Al2O3/SiO2 tunnel barrier composed of dielectrics with different band gaps and electron affinities improved the asymmetric I–V characteristics. Photoresponse measurements under AM1.5G illumination revealed a clear photocurrent, indicating rectification-related photoresponse. The photoresponse increased with decreasing junction area, which is consistent with enhanced rectification performance in smaller junctions. These results demonstrate that the GI2G tunnel diode provides a promising platform for next-generation energy harvesting and optical sensing applications.
]]>Authors: Stefano Bellucci
Carbon nanotubes (CNTs) represent promising nanoplatforms for drug delivery due to their high surface area, tunable surface chemistry, and unique physicochemical properties. This study investigated the effect of chemical functionalization on the dispersion, drug loading, release behavior, aerosolization, and preliminary in vitro cytotoxicity of CNT-based drug delivery systems, with a view toward potential intranasal applications. Pristine CNTs and CNTs functionalized with hydroxyl (–OH) and carboxyl (–COOH) groups were loaded with methylene blue as a model therapeutic compound. The nanosystems were characterized using Raman spectroscopy, UV–Vis analysis, aerosol deposition measurements, electrical mapping by conductive atomic force microscopy (C-AFM), and MTT cytotoxicity assays. Functionalization significantly enhanced CNT dispersion stability and drug release control, with COOH–CNTs exhibiting the most sustained release profile and improved cytocompatibility, maintaining cell viability above XX% at concentrations up to YY µg/mL. Aerosolization tests demonstrated stable droplet formation compatible with nasal delivery devices. Overall, this work provides a proof-of-concept physicochemical and technological assessment of functionalized CNTs as potential carriers for intranasal drug delivery, laying the groundwork for future in vivo validation.
]]>Authors: Mingjie Wang Siqing Chen Yue Guo Hengshan Mao Gaoce Han Yu Ding Yuxin Fan Yifei Yu
Lithium-ion batteries (LIBs) power devices from portable electronics to electric vehicles and grid storage, yet their reliable operation requires real-time monitoring of battery state, particularly at the anode where complex reactions and structural changes occur. Sensor technologies capable of capturing dynamic physical and chemical signals have therefore gained increasing attention for probing internal battery processes. This review summarizes recent operando and in situ monitoring strategies for carbon-based and silicon-based anodes, highlighting advances in electrical, optical, and acoustic sensing. These methods reveal degradation mechanisms and morphological evolution in real time. Multimodal sensing strategies that integrate multiple signals for improved battery state estimation are also discussed. Finally, future directions are outlined, focusing on real-time anode monitoring and the integration of sensing technologies with next-generation battery designs. This review aims to guide the development of smart battery sensing for artificial-intelligence-assisted and multimodal sensing, providing solutions for battery management system that enable accurate synchronous detection of mechanical, thermal, and electrical signals.
]]>Authors: María E. Farías Farías Hermosilla Alberto G. Albesa
Halomethanes (CH3X, where X = F, Cl, Br) are potent atmospheric pollutants, and their removal via adsorption on activated carbons (ACs) is a critical remediation strategy. However, the molecular-level influence of AC surface chemistry on adsorption, especially under realistic environmental conditions, is not fully understood. This work utilizes Grand Canonical Monte Carlo (GCMC) simulations to investigate the adsorption of CH3F, CH3Cl, and CH3Br on realistic carbon models, comparing unfunctionalized graphitic surfaces (AC0) with surfaces functionalized with alcohol (AC1), carbonyl (AC2), and carboxyl (AC3) groups. We analyze the process for both pure components and in realistic mixtures (Quarantine and Pre-Shipment concentrations). Our findings reveal a critical inversion in adsorption preference. For pure components, CH3Br adsorption is highest on the unfunctionalized (AC0) surface, driven by strong adsorbate–adsorbate interactions leading to condensation, characterized by a rising isosteric heat of adsorption (Qst≈35–45 kJ/mol) that matches the enthalpy of sublimation. Conversely, in realistic humid mixtures, the pristine surface suffers a capacity collapse (>90% loss). The functionalized surfaces (especially AC3) demonstrate superior performance, exhibiting a thermodynamic selectivity of SCH3Br/Air>100 (compared to S≈15 for AC0) and retaining approximately 60% of their dry-condition affinity. This study elucidates the distinct roles of surface chemistry and intermolecular forces, providing a molecular basis for designing carbon materials optimized for high selectivity in complex environmental gas streams.
]]>Authors: Pedro M. A. Guerreiro Ana Rita G. E. Pires Susana M. C. S. Fidalgo Orlando M. N. D. Teodoro Pedro Costa Pinto Nenad Bundaleski
Monte Carlo simulations of the transport of atoms in gases related to the deposition process and the contamination of amorphous carbon thin films during deposition in magnetron discharges have been performed. These films are of interest in accelerator technology due to their low secondary electron yield when their structures are dominated by sp2 carbon. Two codes, which practically share the same algorithm, are introduced: TAGs 1 simulates the transport of sputtered atoms from the target to the substrate, and TAGs 2 simulates the transport of atoms from the plasma towards the target and the substrate. The similar results of TAGs 1 and the well-established SIMTRA for the same input parameters imply the algorithm’s accuracy. The codes were used to model the transport of different atoms (C, H, O, D) in a magnetron Ar discharge. The simulations reveal that the operating pressure should be higher than 1 Pa for a sample-target distance of 90 mm to secure sp2 carbon formation. The contamination mechanisms of amorphous carbon coatings were then studied by merging the results obtained with both programs. Preliminary comparisons with experiments suggest that the combined results of TAGs 1 and 2 agree very well with the experiments.
]]>Authors: Patrícia S. F. Ramalho Olívia S. G. P. Soares José L. Figueiredo Manuel F. R. Pereira
Reducing emissions of nitrogen compounds represents a significant challenge in environmental protection, and catalytic treatment is an effective approach. Carbon-based catalysts offer a promising alternative by exploiting the redox properties of carbon materials and eliminating the need for external reducing agents. In this study, nitrogen-free and nitrogen-doped activated carbons were used for NO reduction. The catalysts were developed by incorporating transition metals (Cu and Fe), alkali metals (K), and bimetallic Cu-K formulations. The addition of K to Cu and the presence of nitrogen functionalities improved the catalytic performance and an optimum Cu/K ratio was identified. The best-performing catalyst, AC_M_BM@5Cu5K, achieved 100% NO conversion at 410 °C, producing mainly N2 and CO2, while N2O was detected as an intermediate and CO was not observed. The catalyst’s stability was evaluated in a 100 h continuous test at 376 °C, during which the catalyst maintained approximately 90% NO conversion for 40 h before deactivation. The deactivation mechanism is discussed in detail.
]]>Authors: Jihong Liu Hongming Liu
In recent years, the rapid commercialization and widespread adoption of portable and wearable electronic devices have imposed increasingly stringent performance requirements on flexible sensors, including enhanced sensitivity, stability, response speed, comfort, and integration. This trend has driven extensive research and technological advancement in sensor material systems, among which carbon-based materials have emerged as core candidates for high-performance flexible sensors due to their exceptional electrical conductivity, mechanical flexibility, chemical stability, and highly tunable structural features. Meanwhile, new sensing mechanisms and innovative device architectures continue to emerge, demonstrating significant value in real-time health monitoring, early disease detection, and motion-state analysis, thereby expanding the functional boundaries of flexible sensors in the health-care sector. This review focuses on the application progress and future opportunities of carbon-based materials in flexible sensors, systematically summarizing the critical roles and performance-optimization strategies of carbon nanotubes, graphene, carbon fibers, carbon black, and their derivative composites in various sensing systems, including strain and pressure sensing, physiological electrical signal detection, temperature monitoring, and chemical or environmental sensing. In response to the growing demands of modern health-monitoring technologies, this review also examines the practical applications and challenges of flexible sensors—particularly those based on emerging mechanisms and novel structural designs—in areas such as heart-rate tracking, blood-pressure estimation, respiratory monitoring, sweat-component analysis, and epidermal electrophysiological signal acquisition. By synthesizing the current research landscape, technological pathways, and emerging opportunities of carbon-based materials in flexible sensors, and by evaluating the design principles and practical performance of diverse health-monitoring devices, this review aims to provide meaningful reference insights for researchers and support the continued innovation and practical deployment of next-generation flexible sensing technologies.
]]>Authors: Ikbal Adrian Milka Bijak Riyandi Ahadito Desnelli Desnelli Nurlisa Hidayati Muhammad Said
Graphene oxide (GO) and reduced graphene oxide (rGO) have solidified their role as cornerstone nanomaterials in the pursuit of sustainable technology. This review synthesizes recent advances in harnessing the unique properties of GO and rGO such as their tunable surface chemistry and exceptional electrical conductivity for applications spanning environmental remediation and energy storage. In the environmental domain, they function as superior adsorbents and catalysts for the removal of hazardous pollutants. Concurrently, in the energy sector, their integration into supercapacitors and battery electrodes significantly enhances energy and power density. The adaptability of these materials also facilitates the creation of highly sensitive sensors and biosensors. However, the transition from laboratory research to widespread industrial application is hindered by challenges in scalable production, environmental health and safety concerns, and long-term stability. This review enhances the understanding of GO and rGO’s diverse applications and paves the way for future sustainable technologies in energy and environmental sectors.
]]>Authors: Zhi-Yang Fan Xiao-Min Wang Wei-Yi Zhang Li-Ke Cheng Wen-Xiu Gao Cheng-Yong Shu
Lithium thermal batteries are primary reserve batteries utilizing solid molten salt electrolytes. They are regarded as ideal power sources for high-reliability applications due to their high power density, rapid activation, long shelf life, wide operating temperature range, and excellent environmental adaptability. However, existing electrode systems are limited by insufficient conductivity and the use of high-impedance MgO binders. This results in sluggish electrode reaction kinetics and incomplete material conversion during high-temperature discharge, causing actual discharge capacities to fall far below theoretical values. To address this, FeS2-CoS2 multi-component composite cathode materials were synthesized via a high-temperature solid-phase method. Furthermore, two distinct MgO binders were systematically investigated: flake-like MgO (MgO-F) with a sheet-stacking structure and spherical MgO (MgO-S) with a low-tortuosity granular structure. Results indicate that while MgO-F offers superior electrolyte retention via physical confinement, its high tortuosity limits ionic conduction. In contrast, MgO-S facilitates the construction of a wettability-enhanced continuous ionic network, which effectively reduces interfacial impedance and enhances system conductivity. This regulation promoted Li+ migration and accelerated interfacial reaction kinetics. This study provides a feasible pathway for improving the electrochemical performance of lithium thermal batteries through morphology-oriented MgO binder regulation.
]]>Authors: Patrick L. Langlois Chavdar P. Chilev Farida D. Lamari
This study provides a comprehensive overview of research and advancements on carbon materials with regard to practical targets for hydrogen storage in terms of gravimetric and volumetric capacities. For the sake of clarity, only the most relevant references on hydrogen storage by adsorption are presented, although the study was conducted in the same exhaustive manner as the one initially carried out by Anne C. Dillon and Michael J. Heben in 2001 with a particular emphasis on emerging technologies and potential applications in various sectors. This study also focuses on the importance of carbon-based materials with high specific surface areas and porous structures optimised to maximise adsorption—including at high pressure—while primarily limiting references herein to experimentally validated results. It therefore offers insights into the porous materials, as well as the methodologies—including a fully comprehensive and so-far proven highly transferable intermolecular hydrogen model combining van der Waals’s and Coulomb’s forces—used to improve hydrogen solid storage efficiency.
]]>Authors: Luigi Madeo Pietro Figliuzzi Assunta Perri Anastasia Macario Carlo Siciliano Pierantonio De Luca
This study investigates the use of carbon nanotubes (CNTs) in the development of a filter capable of capturing toxic and carcinogenic compounds found in cigarette smoke dispersed in the environment. The aim is to contribute to the reduction in passive exposure to these substances, with potential benefits for public health and air quality. Carbon nanotubes were selected for their exceptional adsorption properties, attributed to their high specific surface area and porous structure. The material’s adsorptive performance was evaluated based on the quantity used, to determine the optimal mass that ensures the best filtering capacity. To test the system, an experimental setup was assembled to simulate real-world smoke emission conditions. Filters containing CNTs were subjected to gravimetric analysis to measure the amount of retained substances, and to gas chromatography to identify the adsorbed chemical compounds. The results confirm the potential of carbon nanotubes as an advanced filtering material, paving the way for robust solutions to mitigate the environmental impact of secondhand smoke. The results indicate that CNT-based filters, particularly those containing 0.06 g of material, are highly effective in retaining several toxic components of cigarette smoke, including nicotine. This configuration achieves a strong reduction in harmful organic species while using a moderate amount of adsorbent, suggesting a promising selectivity of CNTs toward the most hazardous molecules.
]]>Authors: Oluwatoyosi O. Oyebiyi Antonio Laezza Md Muzammal Hoque Sounilan Thammavongsa Meng Li Sophia Tsipas Anastasios J. Tasiopoulos Antonio Scopa Marios Drosos
Soil amendments play a critical role in improving soil health and supporting sustainable crop production, especially under declining soil fertility and climate-related stress. However, their impact varies because each amendment influences the soil through different biogeochemical processes rather than a single universal mechanism. This review synthesizes current knowledge on a wide range of soil amendments, including compost, biosolids, green and animal manure, biochar, hydrochar, bagasse, humic substances, algae extracts, chitosan, and newer engineered options such as metal–organic framework (MOF) composites, highlighting their underlying principles, modes of action, and contributions to soil function, crop productivity, and soil carbon dynamics. Across the literature, three main themes emerge: improvement of soil physicochemical properties, enhancement of nutrient cycling and nutrient-use efficiency, and reinforcement of plant resilience to biotic and abiotic stresses. Organic nutrient-based amendments mainly enrich the soil and build organic matter, influencing soil carbon inputs and short- to medium-term increases in soil organic carbon stocks. Biochar, hydrochar, and related materials act mainly as soil conditioners that improve structure, water retention, and soil function. Biostimulant-type amendments, such as algae extracts and chitosan, influence plant physiological responses and stress tolerance. Humic substances exhibit multifunctional effects at the soil–root interface, contributing to improved nutrient efficiency and, in some systems, enhanced carbon retention. The review highlights that no single amendment is universally superior, with outcomes governed by soil–crop context. Its novelty lies in its mechanism-based, cross-amendment synthesis that frames both yield and carbon outcomes as context-dependent rather than universally transferable. Within this framework, humic substances and carbon-rich materials show potential for climate-smart soil management, but long-term carbon sequestration effects remain uncertain and context-dependent.
]]>Authors: Jialiang Liu Xiaoxuan Zhang Jiaxuan Gao Xuanhe Liu
With the dual challenges of global energy scarcity and worsening environmental issues, the efficient and selective conversion of CO2 into CH4-an environmentally friendly fuel with high energy density—offers considerable application potential. In this study, a 2D-Cu2O/carbon nitride (2D-Cu2O/CN) heterojunction catalyst was successfully prepared. Notably, 2D-Cu2O/CN shows enhanced light absorption capacity, reduced charge-transfer resistance, and efficient separation of photogenerated electron–hole pairs. It exhibits a CH4 yield of 14.1 μmol·g−1·h−1, 4-fold higher than that of CN. This study provides a feasible approach for the design of high-efficiency photocatalysts for CO2 reduction to CH4.
]]>Authors: Zayda V. Herrera-Cuadrado Lizeth J. Bastidas-Solarte Erwin García-Hernández Adrián Bonilla-Petriciolet Carlos J. Duran-Valle Didilia I. Mendoza-Castillo Hilda E. Reynel-Ávila Ma. del Rosario Moreno-Virgen Gloria Sandoval-Flores Sofía Alvarado-Reyna
This manuscript reports the preparation, surface characterization, and modeling of chars and activated carbons obtained from avocado biomass for hydrogen storage. Activated carbons were prepared from avocado biomass via the following stages: (a) pyrolysis of avocado biomass, (b) impregnation of the avocado-based char using an aqueous lithium solution, and (c) thermal activation of lithium-loaded avocado char. The synthesis conditions of char and activated carbon samples were tailored to maximize their hydrogen adsorption properties at 77 K, where the impact of both pyrolysis and activation conditions was assessed. The hydrogen storage mechanism was discussed based on computational chemistry calculations and multilayer adsorption simulation. The modelling focuses on the analysis of the saturation of activated carbon active sites via the adsorption of multiple hydrogen molecules. The results showed that the activated carbon samples displayed adsorption capacities higher than their char counterparts by 71–91% because of the proposed activation protocol. The best activated carbon obtained from avocado residues showed a maximum hydrogen adsorption capacity of 142 cm3/g, and its storage performance can compete with other carbonaceous adsorbents reported in the literature. The hydrogen adsorption mechanism implied the formation of 2–4 layers on activated carbon surface, where physical interactions via oxygenated functionalities played a relevant role in the binding of hydrogen dimers and trimers. The results of this study contribute to the application of low-cost activated carbons from residual biomass as a storage medium in the green hydrogen supply chain.
]]>Authors: Miguel Garcia-Rollan Miguel Miranda Silvia Ponce Carolina Belver Jorge Bedia
In this study, removal of nicotine, highly toxic and persistent environmental contaminant, was successfully conducted using activated carbons prepared via chemical activation with KOH from shrimp shell, a byproduct of the food industry. The activation process yielded activated carbons with an exceptionally developed porous texture, exhibiting, in the best case, a surface area of nearly 2000 m2/g and a surface enriched with diverse oxygenated functional groups, as confirmed by XPS and FTIR analyses. Nicotine adsorption studies demonstrated that the adsorption process was more favorable at near-neutral pH values (pH = 8) and higher temperatures. Kinetic and thermodynamic analyses, combined with material characterization, revealed that the adsorption process is governed by both physical and chemical interactions between the adsorbate and the adsorbent, being overall spontaneous and endothermic. The Sips isotherm model closely fits the adsorption data, highlighting the heterogeneity of the activated carbon surface. Under these conditions, adsorption was studied at three different temperatures, with the highest temperature (45 °C) exhibiting the most significant adsorption capacity, slightly below 500 mg/g. In addition, column adsorption tests demonstrated the high efficiency of activated carbons in nicotine removal, making shrimp head shells a promising carbon precursor for use as a raw material in preparing activated carbons for use as nicotine adsorbents for industry.
]]>Authors: Solange Amigues Natalia Krasteva Kamelia Hristova-Panusheva Milena Keremidarska-Markova Giorgio Speranza Firas Awaja
Graphene oxide (GO)-based nanomaterials hold significant potential for targeted cancer therapy owing to their tunable physicochemical properties and surface versatility. In this study, we systematically evaluated the cytotoxicity of pristine GO (graphene oxide) and its surface-functionalized derivatives, GO-CH4 (methyl), GO-NH2 (amine), and GO-O2 (carboxyl), against murine Colon 26 carcinoma cells. Cell morphology, adhesion, and proliferation were assessed after three days of exposure using fluorescein diacetate (FDA) live/dead staining and the WST-1 mitochondrial activity assay. Distinct material-dependent biological responses were observed: GO-CH4 (methyl) and GO-O2 (carboxyl) exhibited pronounced cytotoxicity, reducing cell adhesion and proliferation by more than 50% relative to controls, whereas GO-NH2 (amine) induced only moderate effects. Pristine GO (graphene oxide) showed minimal impact on cell viability and morphology, consistent with its limited cellular internalization. These results demonstrate that surface functionalization critically governs GO (graphene oxide) biocompatibility and cytotoxicity, underscoring its potential as a tunable platform for developing graphene-based cancer therapeutics, implant coatings, and biointerfaces with controlled cellular responses.
]]>Authors: Pascal Puech Sébastien Moyano Petros Mubari Elsa Weiss-Hortala Marc Monthioux
Removing background signals is a common preprocessing step, but it is not without drawbacks. In X-ray diffraction data, background correction can artificially symmetrize diffraction peaks, which becomes a critical issue for lamellar materials such as graphenic carbon when the Laue indices lie in the plane (e.g., the 10 and 11 peaks). We discuss several approaches to background correction and their implications for the resulting data. In Raman spectroscopy, defects activate the phonon density of states, leading to higher intensity below the D band than above the G band, with respect to the Raman shift. After discussing the linear and circular polarization on the Raman selection rules, we show how flattening the background—a widely used measure of disorder—alters the ID/IG ratio. Finally, principal component analysis (PCA) provides a useful preliminary exploration of data structure; however, because its components may include negative contributions, it cannot be directly applied to spectral decomposition. In contrast, non-negative component decomposition offers an optimal way to preserve the Raman background, even in the presence of luminescence. We confirm our analysis with ANOVA p-values.
]]>Authors: Moath Al Hayek Aayush Patel Joshua Ellison Jungkyu Park
In the present study, molecular dynamics simulations with three interatomic potentials (Polymer Consistent Force Field, Adaptive Intermolecular Reactive Empirical Bond Order, and Tersoff) are employed to investigate strain-dependent interfacial thermal resistance across one-dimensional to two-dimensional junctions. Carbon nanotube–graphene junctions exhibit exceptionally low interfacial resistances (1.69–2.37 × 10−10 K·m2/W at 300 K)—two to three orders of magnitude lower than conventional metal–dielectric interfaces. Strain-dependent behavior is highly potential-dependent, with different potentials showing inverse, positive, or minimal strain sensitivity. Local phonon density of states analysis with Tersoff reveals that strain-induced spectral redistribution in graphene toward lower frequencies enhances phonon coupling with carbon nanotube modes. Temperature significantly affects resistance, with 37–59% increases at 10 K compared to 300 K due to long-wavelength phonon scattering. Boron nitride nanotube–hexagonal boron nitride nanosheet junctions exhibit 60% higher resistance (3.2 × 10−10 K·m2/W) with temperature-dependent strain behavior and spacing-insensitive performance. Interfacial resistance is independent of pillar height, confirming junction-dominated transport. The discovery of exceptionally low interfacial resistances and material-specific strain responses enables the engineering of thermally switchable devices and mechanically robust thermal pathways. These findings directly address critical challenges in next-generation flexible electronics where devices must simultaneously manage high heat fluxes while maintaining thermal performance under repeated mechanical deformation.
]]>Authors: Lok Kumar Shrestha Sarita Manandhar Sabina Shahi Rabindra Nath Acharyya Aabha Puri Chhabi Lal Gnawali Rinita Rajbhandari Katsuhiko Ariga
This study reports the synthesis of an activated nanoporous carbon material from Phyllanthus emblica (Amala)—a biomass material which is an eco-friendly, economical, and sustainable precursor used to prepare activated carbon using zinc chloride (ZnCl2) activation at various temperatures (500–700 °C) under a nitrogen gas atmosphere. A sample that was carbonized at 700 °C (AmC_Z700) attained a high specific surface area of 1436 m2 g−1 and a total pore volume of 0.962 cm3 g−1, and, when used in an electrode, showed excellent supercapacitance performance, attaining a high specific capacitance of 263 F g−1 at a current density of 1 A g−1, followed by 55% capacitance retention at 50 A g−1. Additionally, the assembled symmetric supercapacitor cell, when operated at 1.2 V, delivered an energy density of 8.9 Wh kg−1 at a power density of 300 W kg−1 and exhibited an excellent cycle life of 95% after 10,000 successive charge/discharge cycles, demonstrating the substantial potential of Phyllanthus emblica seed-derived carbon materials for the creation of high-performance supercapacitors.
]]>Authors: Yue Wang Jiayao Gao Cuiluan Ma Yucai He
In this work, a novel polyvinyl alcohol/starch (PVA/St)-based composite film was fabricated by integrating citric acid (CA) and silver-loaded biochar (C-Ag) nanofillers to enhance antibacterial functionality. Sorghum straw-derived biochar was loaded with silver nanoparticles (AgNPs) through a green synthesis route using Peucedanum praeruptorum Dunn extract. The successful crosslinking by CA and the uniform incorporation of AgNPs were confirmed by FTIR, XRD, and SEM. Notably, the optimized composite film containing 1.5 g/L C-Ag exhibited strong broad-spectrum antibacterial activity, with inhibition zones of 28 mm against E. coli, 29 mm against S. aureus, and 26 mm against P. aeruginosa, respectively. The high efficacy is attributed to the synergistic effect between the sustained release of Ag+ and the CA-induced acidic microenvironment. This work provides a green and high-performance antibacterial material to address the potential microbe contamination.
]]>Authors: Ying-Pin Huang Chung-I Chen Chih-Pei Shen Jia-Yi Shen Wei-Chih Chen Yue-Hua Liou Shih-Chi Lee Chuan-Chi Chien Xu-Chen Yang Wen-Hung Huang Ching-Wen Wang
This study evaluated the seasonal greenhouse gas (GHG) emissions and carbon assimilation of Bambusa edulis under four soil amendment treatments—control (C), biochar (B), fertilizer using vermicompost (F), and biochar plus fertilizer (B + F)—in a coastal shelterbelt system in south-western Taiwan. Over a 12-month period, CO2 and N2O fluxes and photosynthetic carbon uptake were measured. The control (C) treatment served as the baseline, exhibiting the lowest greenhouse gas (GHG) emissions and carbon assimilation. Its summer N2O emissions were 39.54 ± 20.79 g CO2 e m−2, and its spring carbon assimilation was 13.2 ± 0.84 kg CO2 clump−1. In comparison, the amendment treatments significantly enhanced both emissions and carbon uptake. The fertilizer-only (F) treatment resulted in the highest levels, with peak summer N2O emissions increasing by 306.5% (to 160.73 ± 96.22 g CO2 e m−2) and spring carbon assimilation increasing by 40.2% (to 18.5 ± 0.62 kg CO2 clump−1). An increase in these values was also observed in the combined biochar and fertilizer (B + F) treatment, although the magnitude was less than that of the F treatment alone. In the B + F treatment, summer N2O emissions increased by 130.3% (to 91.1 ± 62.51 g CO2 e m−2), while spring carbon assimilation increased by 17.4% (to 15.5 ± 0.36 kg CO2 clump−1). Soil CO2 flux was significantly correlated with atmosphere temperature (r = 0.63, p < 0.01) and rainfall (r = 0.45, p < 0.05), while N2O flux had a strong positive correlation with rainfall (r = 0.71, p < 0.001). The findings highlight a trade-off between nutrient-driven productivity and GHG intensity and demonstrate that optimized organic and biochar applications can enhance photosynthetic carbon gain while mitigating emissions. The results support bamboo’s role in climate mitigation and carbon offset strategies within nature-based solution frameworks.
]]>Authors: Guihe Li Jun He Jia Yao
With the intensifying global climate crisis and the urgent demand for carbon neutrality, carbon dioxide (CO2) capture technologies have received growing attention as effective strategies for mitigating greenhouse gas emissions. Carbon-based porous materials are widely regarded as promising CO2 adsorbents due to their tunable porosity, high surface area, and excellent chemical and thermal stability. Among them, biomass-derived porous carbon materials have received growing attention as sustainable, low-cost alternatives to fossil-based adsorbents. This review provides a comprehensive overview of recent advances in biomass-derived porous carbon materials for CO2 capture, emphasizing the fundamental adsorption mechanisms, including physisorption, chemisorption, and their synergistic effects. Key synthesis pathways, such as pyrolysis and hydrothermal carbonization, are discussed in relation to the development of biomass-derived porous carbon materials. Furthermore, performance-enhancing strategies, such as activation treatments, heteroatom doping, and templating methods, are critically evaluated for their ability to tailor surface properties and improve CO2 uptake capacity. Recent progress in typical biomass-derived porous carbon materials, including active carbon, hierarchical porous carbon, and other innovative carbon materials, is also highlighted. In addition to summarizing recent advances in porous carbon synthesis, this review introduces a unified techno-economic framework that integrates cost, sustainability, and performance-driven benefits. Overall, this review aims to provide systematic insights into the performance of biomass-derived porous carbon materials and to guide the rational design of efficient, sustainable adsorbents for real-world carbon capture applications.
]]>Authors: Aika Harako Shuhei Shimoda Keita Suzuki Atsushi Fukuoka Tomoya Takada
The photocatalytic efficiency of graphitic carbon nitride (g-C3N4) for the decomposition of aqueous rhodamine B (RhB) was investigated. To examine the combined effects of sonication and electron beam (EB) irradiation on the photocatalytic efficiency, g-C3N4 was sonicated in 1,3-butanediol and subsequently irradiated with EB. The photocatalytic efficiency was improved by the low-dose EB irradiation due to the generation of structural defects that acted as active reaction sites. Sonication before EB irradiation induced mild exfoliation and further improved photocatalytic efficiency. Prolonged sonication enhanced this improvement, primarily by increasing the specific surface area of g-C3N4. The positive effect of sonication was more remarkable for g-C3N4 irradiated with low-dose EB than for g-C3N4 irradiated with higher-dose EB. The photocatalytic RhB decomposition rate measured for g-C3N4 sonicated for 480 min and irradiated at 200 kGy was approximately 6.8 times higher than that measured for the untreated g-C3N4. The difference between the sonication effects can be ascribed to the electrostatic interactions and the resultant agglomeration of the g-C3N4 particles after EB irradiation. High-dose EB irradiation caused electrification followed by coarsening of the particles, whereas low-dose EB irradiation did not produce these results and led to positive effects due to the EB-induced g-C3N4 structural alteration.
]]>Authors: Wen-Huan Qiao Ya-Ni Liu Ya Li Yu Xie Hai-Yi Yang Jun-Wei Hou
Flow capacitive deionization (FCDI) technology holds significant promise for cost-effective and energy-efficient desalination; however, its practical application is hindered by limited electrode stability and desalination performance. In this study, we propose a novel composite strategy that combines chemical surface modification with surfactant-assisted dispersion to enhance electrode performance in FCDI systems. We observed that the dispersion stability and capacitance of the flow electrodes were significantly improved after oxidation (AC-O) or amination (AC-N) of activated carbon (AC). To further investigate the underlying ion adsorption mechanisms, we performed Density Functional Theory (DFT) simulations. The simulations revealed that oxidative modification (AC-O) enhances chloride ion adsorption through stronger electrostatic and van der Waals interactions, while amination (AC-N) is more effective for sodium ion adsorption. Subsequently, surfactants (sodium dodecyl sulfate, SDS; cetyltrimethylammonium bromide, CTAB) were used to prepare stable and high-performance flow electrodes. Electrochemical characterization and desalination tests in a 1000 mg·L−1 saline solution demonstrated that the AC-O/SDS composite exhibited excellent dispersion stability (>7 d) and significantly enhanced conductivity and specific capacitance, increasing by factors of 2.48 and 2.50, respectively, compared to unmodified AC. This optimized electrode achieved a desalination efficiency of 74.37% and a desalination rate of 6.2542 mg·L−1·min−1, outperforming the unmodified electrode by a factor of 5.72. Our findings provide a robust, sustainable approach for fabricating advanced flow electrodes and offer valuable insights into electrode structure optimization, opening new possibilities for the application of FCDI technology in water treatment and material sciences.
]]>Authors: Henryk A. Witek Rafał Podeszwa
We demonstrate that the energetic stability of carbon (5,6)-fullerene isomers can, to a large extent, be inferred from two topological invariants: the Kekulé count K and the Clar count C. Although neither invariant alone exhibits a strong correlation with the total electronic energy at equilibrium geometry, the application of a min–max principle (maximizing C while minimizing K) proves effective in identifying the lowest-energy subset of Cn isomers for n= 50–100. This finding substantially reduces the complexity of determining the most stable isomer among larger fullerenes.
]]>Authors: Alberto Maria Gambelli Daniela Pezzolla Federico Rossi Giovanni Gigliotti
This study explores the production of hydrates with binary (CH4/C2H6) gaseous mixtures, varying the concentration of each species from 25 to 75 vol%. The thermodynamics of this process are explored in detail, and the achieved results are explained in terms of cage occupancy and compared with the phase boundary equilibrium conditions of pure methane and pure ethane hydrates. The addition of ethane is found to not contribute significantly to the quantity of gas captured in hydrates. Conversely, it delays the massive growth of hydrates, shifting the process towards conditions supporting the formation of pure methane hydrates. The presence of C2H6 molecules within the hydrate lattices improved their overall stability and avoided the dissociation of water cages even under temperature increases (from the conditions measured at the end of formation) up to 14.40 °C. This latter property makes ethane a viable support species for the solid storage of energy gases in the form of hydrates.
]]>Authors: Przemysław Pączkowski Viktoriia Kyshkarova Sergii Guzii Inna Melnyk Barbara Gawdzik
This study focuses on a single-step microwave-assisted carbonization and activation method for biomasses derived from peanut shells and spruce cones. Using phosphoric acid as the activating agent, this process leads to carbon materials with a micro-mesoporous structure, favoring dye adsorption. Elemental and surface analyses confirmed that the physicochemical properties of the obtained carbons are strongly dependent on the biomass’ source. The carbon materials obtained in this way, differing in porous structure and the presence of functional groups on their surfaces, were used for static adsorption of hazardous dye crystal violet from water. The adsorption behavior of both materials fits well with the Langmuir and Freundlich isotherms, indicating a combination of monolayer and heterogeneous surface adsorption, driven primarily by physical interactions. Of these two materials, carbon derived from spruce cones was characterized by better porosity, higher surface functionality, and higher adsorption capacity, demonstrating its potential as a cost-effective and sustainable material for wastewater treatment applications.
]]>Authors: Weiyun Chen Ivan Cole Andrew S. Ball Hong Yin
The removal of synthetic dyes from industrial effluents remains challenging due to their chemical stability and poor biodegradability. Here we engineer metal-doped carbon dots (CDs) as heterogeneous Fenton-like catalysts and elucidate how dopant identity governs structure–activity relationships and reactive oxygen species (ROS) pathways. Fe-, Cu-, Zn- and Mg-doped CDs were prepared via a one-pot hydrothermal route and comprehensively characterised by TEM, FTIR, XPS and zeta-potential analysis. The resulting nanoparticles displayed narrow size distributions (10.2–15.2 nm) and dopant-dependent surface chemistries and charges. Catalytic tests with methylene blue (MB) and rhodamine B (RB) show that Fe-doped CDs deliver the highest activity toward MB degradation (k = 0.0218 min−1), attributable to efficient Fe2+/Fe3+ redox cycling coupled with hydroxyl-rich surfaces that promote H2O2 activation. Zn-doped CDs achieve complete RB decolourisation under Fenton-like conditions, which we ascribe to their higher surface charge and abundant oxygenated sites that enhance pollutant adsorption and ROS generation. Cu- and Mg-doped CDs exhibit intermediate and dopant-specific performances consistent with their respective redox and adsorption characteristics. Collectively, these results establish clear correlations between dopant chemistry, surface functionality, and ROS formation routes, providing mechanistic guidance for the rational design of carbon-based Fenton catalysts for sustainable water remediation.
]]>Authors: Thais da Silva Thiély da Silva Rieyssa Corrêa Rui Ribeiro Guilherme Morgado Larissa Montagna Braian Uribe Maraisa Goncalves Michelle Costa Fabio Passador Maria Conceição Paiva Edson Botelho
Hybrid buckypapers (BPs) composed of graphene nanoplatelets (GNPs) and carbon nanotubes (CNTs) hold great potential for applications in flexible electronics, electromagnetic shielding, and energy storage. In this study, hybrid BPs were fabricated and characterized to evaluate their structural, thermal, and electrical properties. Hybrid BPs with varying GNP/CNT mass ratios (0/100, 25/75, 50/50, 75/25, 85/15, 90/10, and 95/5 wt%) were prepared via vacuum-assisted filtration of well-dispersed aqueous suspensions stabilized by surfactants. The resulting hybrid GNP/CNT BPs were dried and subjected to post-treatment processes to enhance structural integrity and electrical performance. Characterization techniques included scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared (FT-IR), Raman spectroscopy, thermogravimetric analysis (TGA), nitrogen adsorption/desorption isotherms, and impedance spectroscopy (IS). The hybrid GNP/CNT BPs exhibited electrical conductivities comparable to conventional CNT-based BPs. At GNP concentrations of 25 to 50 wt%, electrical conductivity values approached those of CNT-based BPs, while at GNP concentrations between 75 and 90 wt%, a slight increase in conductivity was observed (171%). These results highlight a synergistic effect at lower CNT concentrations, where the combination of CNTs and GNPs enhances conductivity. The findings suggest that optimal conductivity is achieved through a balanced incorporation of both materials, offering promising prospects for advanced BP applications.
]]>Authors: Liang Xu Jie Peng Zhaoyang Niu Wenbin Li Donghui Zhang
Carbon dioxide emissions, particularly from large point sources such as fossil-fuel power plants, represent a primary driver of global warming. Although various carbon-based adsorbents have been developed for carbon capture applications, most existing materials exhibit limited CO2 adsorption capacity at flue gas-relevant partial pressures and are susceptible to interference from impurity components. In this study, a series of nitrogen-doped carbons was prepared from commercial phenolic resin and melamine via a two-step carbonization–activation process. The effects of precursor-to-dopant ratio and thermal conditions on CO2 adsorption were systematically investigated. The results indicated that CO2 uptake was influenced by specific surface area, nitrogen content, micropore volume, and total pore volume, with a maximum adsorption capacity of 2.455 mmol·g−1 and selectivity over 28 at 25 °C and 1 bar. The series also exhibited excellent cycling stability (<1% loss after 5 cycles) and fast kinetics (>90% uptake within 3 min), suggesting its potential applicability in flue gas CO2 capture.
]]>Authors: Gaukhar Smagulova Aigerim Imash Akniyet Baltabay Aruzhan Keneshbekova Alisher Abdisattar Ramazan Kazhdanbekov Aidos Lesbayev Zulkhair Mansurov
This study presents a comparative analysis of two synthesis approaches for fabricating magnetic sorbents based on activated carbon (AC) incorporated with magnetite (Fe3O4) nanoparticles: hydrothermal synthesis and ultrasonic treatment. The results demonstrate that ultrasonic-assisted synthesis yields a magnetically responsive composite, us-AC/Fe3O4, exhibiting a Pb2+ removal efficiency of 92.84%, which is comparable to that of pristine activated carbon (99.0%). A key advantage of the synthesized composite lies in its facile recovery via magnetic separation following adsorption, rendering it a promising candidate for the remediation of heavy metal-contaminated water. Kinetic modeling suggests a dual adsorption mechanism: initial stages are governed by physisorption, while chemisorption dominates in the later phases. Adsorption isotherm modeling demonstrated that the Langmuir model provided the best description of Pb2+ adsorption on AC and us-AC/Fe3O4, with the highest sorption capacities observed for pristine activated carbon, followed by the ultrasonically modified composite, and comparatively lower values for the hydrothermally treated material. These findings underscore the potential of ultrasonic processing as an effective route for developing magnetically separable sorbents with high performance in aqueous heavy metal removal.
]]>Authors: Yuxuan Du Jian Wang Peihua Li Yalong Wang Yibo Zhao Shuwei Chen
The high-efficiency and clean utilization of coal resources is a key strategy for new energy development, and converting coal into carbon materials offers a promising route to valorize bituminous coal. However, fabricating high-performance bituminous coal-derived carbon for sodium ion (Na+) insertion/extraction remains a major challenge, as it is difficult to regulate the carbon’s microstructural properties to match Na+ storage demands. Herein, we propose a molten salt-assisted carbonization strategy to prepare bituminous coal-derived hard carbon (HC) for use as a sodium-ion battery (SIB) anode material, and we focus on regulating the structure of carbon. The results show that as-prepared HC exhibits significantly enhanced electrochemical performance for Na+ storage when the molar ratio of NaCl to KCl is 1:1. The optimized material achieves a reversible capacity of 366.7 mAh g−1 at the current density of 100 mA g−1 after 60 cycles and retains 99% of its initial capacity after 500 cycles at a current density of 1 A g−1. The main finding is that the lattice spacing can be regulated by tuning the composition of the molten salt, and anode performance is enhanced remarkably by changes in the HC structure. This work provides a feasible strategy for designing and preparing a bituminous coal-derived carbon anode material for use in the energy storage field.
]]>Authors: Boyun Guo Muhammad Towhidul Islam Vincent Nana Boah Amponsah
Injecting carbon dioxide (CO2) into underground geo-structures, such as depleted oil and gas reservoirs, reduces man-made CO2 emissions into the atmosphere or removes what is already there. Studies have identified the risks of CO2 leaks from these underground geo-structures through wellbores back into the atmosphere due to the high mobility of CO2 in gaseous and supercritical states. This work aims at proposing a novel method of CO2 storage using the Joule–Thomson cooling effect to effectively produce CO2 hydrates on seafloors, with an objective to avoid the leakage risks of storage in depleted oil and gas reservoirs. Through the combination of thermodynamic data, analysis of hydrate stability, and engineering design with established working parameters, this study proposes an innovative concept and an enabling process for CO2 placement onto seafloors for safe storage. The results of case analysis of typical seawater conditions reveal that the appropriate seafloor depth ranges for different applications (>1900 m for liquid CO2 and 700–1900 m for CO2 hydrate). An engineering design procedure for real applications is outlined.
]]>Authors: Arturo Tepale-Cortés Hilda Moreno-Saavedra Marquidia J. Pacheco Joel O. Pacheco Celso Hernández-Tenorio Ricardo Valdivia
Electrodes and electrolytes are critical components for the performance of supercapacitors. In this study, supercapacitors with different interfaces were assembled using polypyrrole (PPy) or a polypyrrole–carbon nanotube (PPy-CNT) composite as active materials, and dimethyl sulfoxide (DMSO) and sodium chloride (NaCl) were used as electrolytes. Electrochemical measurements were obtained by cyclic voltammetry (CV) at a scan rate of 20 mV/s and galvanostatic charge–discharge (GCD) measurements at a scan rate of 50 µA/s. The results suggest that the supercapacitor with a PPy-CNT composite and NaCl electrolyte has promising electrochemical characteristics.
]]>Authors: Maria Nikitina Stepan Devyatov Mikhail Rayev
Due to their unique physicochemical properties, carbon black nanoparticles represent a promising alternative for solving analytical problems. However, diagnostic reagents based on carbon black nanoparticles have not yet found widespread practical application. This review examines the development and application of carbon black nanoparticle conjugates with recognition molecules as diagnostic reagents in test systems that enable non-instrumental interpretation of results. The review critically evaluates the methods for synthesis and characterization of carbon black-based diagnostic reagents. Furthermore, the review summarizes and discusses existing studies comparing the effectiveness of carbon black nanoparticle-based bioconjugates with traditional colorimetric labels. The scientific articles included in the review were carefully analyzed for the presence of an assessment of the reproducibility of methods for obtaining diagnostic reagents based on carbon black nanoparticles and their long-term storage. The main challenges and future prospects of using carbon black nanoparticles in immunoassays are discussed.
]]>Authors: Peter J. F. Harris
Non-graphitising carbons are an important class of solid carbon materials which cannot be transformed into graphite by heat treatment, even at 3000 °C. Also known as hard carbons, they are of growing importance as anode materials for lithium-ion or sodium-ion batteries. When activated they are widely used in the purification of air and water supplies. However, despite decades of research, the detailed atomic structures of these materials has still not been fully established. Many structural models have been put forward, beginning with the classic work of Rosalind Franklin, but none have gained universal acceptance. This review gives a historical survey of models for the structure of non-graphitising carbons and summarizes the latest thinking on the subject, which is based on the idea that the structure contains non-hexagonal rings, as in the fullerenes and fullerene-related structures. Studies using aberration-corrected transmission electron microscopy have provided important support for this idea.
]]>Authors: Tetyana I. Melnychenko Vadim M. Kadoshnikov Oksana M. Arkhipenko Tetiana I. Nosenko Iryna V. Mashkina Lyudmila A. Odukalets Sergey V. Mikhalovsky Yuriy L. Zabulonov
Among the main man-made water pollutants that pose a danger to the environment are oil products, heavy metals, and radionuclides, as well as micro- and nanoplastics. To purify such waters, it is necessary to use advanced methods, with sorption being one of them. The aim of this work is to develop a nano-functionalized composite, comprising magnetically responsive, thermally expanded graphite (TEG) and the natural clay bentonite, and to assess its ability to purify man-made contaminated waters. Throughout the course of the research, the methods of scanning electron microscopy, optical microscopy, dynamic light scattering, radiometry, and atomic absorption spectrophotometry were used. The use of the TEG–bentonite composite for the purification of the model water, simulating radioactively contaminated nuclear power plant (NPP) effluent, reduced the content of organic substances by 10–15 times, and the degree of extraction of cesium, strontium, cobalt, and manganese was between 81.4% and 98.8%. The use of the TEG–bentonite composite for the purification of real radioactively contaminated water obtained from the object “Shelter” (“Ukryttya” in Ukrainian), in the Chernobyl Exclusion Zone, Ukraine, with high activity, containing organic substances, including micro- and nanoplastics, reduced the radioactivity by three orders of magnitude. The use of cesium-selective sorbents for additional purification of the filtrate allowed for further decontamination of radioactively contaminated water with an efficiency of 99.99%.
]]>Authors: Anna O. Krasnova Nadezhda V. Glebova Andrey A. Nechitailov Angelina G. Kastsova Anna O. Pelageikina Demid A. Kirilenko Alexander V. Shvidchenko Mikhail S. Shestakov Aleksandra V. Koroleva Ekaterina K. Khrapova
This work presents a comparative study of graphene exfoliation technologies from various graphite precursors—spectral graphite and thermally expanded graphite (Graflex)—using ultrasonic treatment and electrochemical methods in the presence of the ionic surfactant Nafion. The influence of exfoliation parameters, the nature of the starting material, and the presence of surfactant additives on the morphology, dispersibility, stability, and structural characteristics of the resulting graphene-containing dispersions was investigated. Particular attention is paid to a two-step technology combining pulsed electrochemical exfoliation with subsequent mild ultrasonic treatment. Comprehensive characterization of the samples was carried out using UV–Vis spectroscopy, X-ray diffraction (XRD), thermogravimetric analysis (TGA), electron microscopy, electron diffraction (ED), dynamic light scattering (DLS), and X-ray photoelectron spectroscopy (XPS). It was found that the use of Nafion significantly enhances exfoliation efficiency and contributes to the stabilization of the dispersions. Graphene sheets obtained from Graflex exhibit significantly larger lateral dimensions (up to 1 μm or more) compared to those exfoliated from spectral graphite (100–300 nm). The approach combining the use of Graflex and pulsed electrochemical exfoliation in the presence of Nafion with subsequent low-power ultrasonic treatment enables the production of few-layer graphene (1–3 layers) with high stability.
]]>Authors: Miaomiao Ye Jingqiu Wu Qiuyuan Weng Tengchao Bi Xiaowei Liu
The utilization of carbon dioxide (CO2) offers an effective approach for alleviating the carbon-reduction pressures associated with fossil energy consumption. However, studies on the use of CO2 as an auxiliary agent in water treatment to enhance the removal of emerging contaminants are limited. In this study, the photodegradation of ciprofloxacin (CIP) was investigated using ultraviolet (UV) irradiation combined with CO2 dosing (UV/CO2). The results demonstrated that the UV/CO2 system effectively degraded CIP, with CO2 concentration and solution pH exerting a critical influence. Inorganic anions and metal cations had negligible effects on CIP degradation efficiency, whereas natural organic matter (NOM) had a pronounced inhibitory effect. Mechanistic analysis revealed that superoxide radicals (·O2-) and carbonate radicals (CO3•-) were the primary oxidizing species, whereas the excited triplet state of CIP (3CIP*) and singlet oxygen played crucial roles in initiating radical generation. LC–MS analysis and density functional theory calculations indicated that the main degradation routes involved defluorination, decarboxylation, and epoxidation of the piperazine ring. Toxicity assessment indicated that the transformation products generated by UV/CO2 were less toxic than the parent compound. Furthermore, the UV/CO2 process demonstrated high energy efficiency, with a low electrical energy per order (EEO) value of 0.4193 kWh·m−3·order−1. These findings suggest that the UV/CO2 system is a promising alternative for the treatment of photosensitive organic pollutants and provides a beneficial pathway for CO2 utilization.
]]>Authors: Oleg A. Streletskiy Ilya A. Zavidovskiy Vladimir A. Baidak Anatoly S. Pashchina Abdusame A. Khaidarov Vladimir L. Bychkov
Carbyne, a linear chain of carbon atoms, possesses extraordinary properties but has remained elusive due to its extreme instability. While encapsulation within carbon nanotubes stabilizes carbyne, a lack of synthetic control over its location has prevented practical use. Here, we introduce a spatially localized plasma jet technique that enables the guided spatially selective self-assembly of carbyne encapsulated within multiwalled carbon nanotube (carbyne@MWCNT) hybrids on graphite surfaces. This method uses intense, localized plasma energy to simultaneously grow nanotubes and synthesize carbyne within them, where the nanotube structure and carbyne encapsulation are governed by the localized heat flux distribution. Beyond confirming carbyne formation via its characteristic Raman mode, we discover its second-order vibrational spectrum, confirming anharmonic interactions between the chain and its nanotube container. This spatial control can be used to architect functional carbyne@MWCNT arrays, whose potential applications are discussed in detail.
]]>Authors: Angel Maroto-Valiente Carla A. Blanco-Camus Ana I. Mártir Bueno Elena M. Mesa-Bribián Jesús Alvarez-Rodríguez
The controlled incorporation of halogens into carbon materials remains a challenge, particularly under mild and scalable conditions. In this work, we investigate the fixation of iodine on high-surface-area graphite (HSAG-100) using green solvents and moderate temperatures. Commercial HSAG was treated with iodine in aqueous and in organic media, with and without promoters, and characterized by XPS, LEIS, N2 physisorption, TGA/TPD, and XRD. The results reveal that iodine contents up to ~0.6 at% can be achieved, with incorporation strongly influenced by solvent and reaction time. XPS and LEIS confirmed the presence of C–I bonds, while BET analysis showed only moderate decreases in surface area and unchanged mesopore size distribution. Thermogravimetric and TPD analyses demonstrated the high thermal stability of C–I species, and XRD patterns ruled out intercalation between graphene layers. Collectively, these findings demonstrate that iodine can be covalently anchored to HSAG under mild conditions, preserving the graphitic structure and generating stable edge functionalities, thus opening a route for the design of halogen-doped carbons for catalytic and electrochemical applications.
]]>Authors: Xiaomeng Zhu Xiaojun Liu Lihua Li Kun Liu Jian Zhou
Carbide-bonded graphene (CBG) coating, with its unique 3D cross-linked network structure, shows significant potential for protecting silicon substrates. However, a comprehensive understanding of its macroscale tribological properties remains lacking. This study investigated the macroscale friction and wear behaviors of CBG-coated silicon wafers using reciprocating sliding tests against steel balls under various loads and sliding cycles. The CBG coating exhibited excellent friction-reduction and anti-wear performance, reducing the steady friction coefficient from 0.80 to 0.17 and wear rate by an order of magnitude compared to those of bare silicon. Higher loads slightly decreased both friction coefficients and wear rates, primarily due to the formation of denser tribofilms and transfer layers. Re-running experiments revealed three distinct wear stages—adhesive, abrasive, and accelerated substrate wear—driven by the evolution of tribofilms, transfer layers, and unabraded flat areas. Furthermore, comparative experiments confirmed that these “unabraded flat areas” on the wear track play a critical role in sustaining low friction and prolonging coating life. The findings identify CBG as a robust solid lubricant for high-contact-pressure applications and emphasize the influence of tribo-layer dynamics and wear debris behavior on coating performance.
]]>Authors: Haiquan Liu Qiang Guo Yong Chen Yifan Zhang Binbin Huo Meng Li
Coal-based solid wastes are used for carbon fixation, which can achieve the dual purpose of resource utilization of coal-based solid wastes and CO2 storage, but carbon fixation has a negative impact on the rheological properties of filling slurry. This paper explores the effect of carbon fixation time on the carbon fixation performance and rheological properties of coal gangue (CG)–fly ash (FA) composite filling materials (CFS) through rheometer, X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, and other testing methods. The results show that, with an increase in the carbon fixation time, the carbon fixation amount of the CFS shows a trend of increasing first and then stabilizing. Considering the carbon fixation amount and rheological properties of the CFS together, the optimal carbon fixation time is 2 h. At this time, the carbon fixation amount of the CFS is 1.18%, and the yield stress and plastic viscosity are 155.93 Pa and 0.17 Pa·s, respectively. However, with a further increase in the carbon fixation time, the carbon fixation amount basically tends to be stable, mainly because the calcium ions in the CFS are gradually consumed by the reaction as the carbon fixation time increases. The research results are of great significance for improving the utilization of coal-based solid waste and CO2 storage.
]]>Authors: Yan Yang A-Min Tan Qiu-Xuan Ren Gai Zhang
The hierarchical porosity and active sites of porous carbon materials have significant impacts on the oxygen reduction reaction (ORR) process. The heteroatom-doped porous carbon materials (Z67-900, Z8-900, Z11-900, Z12-900) were synthesized by pyrolysis of ZIFs to reveal the synergistic effect of hierarchical porosity and Co-Nx sites. The structures of prepared materials were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Raman spectra, and nitrogen adsorption. The results of electrocatalytic performance show that Z67-900 has the best performance among the four materials prepared. The onset potential (E0) of Z67-900 is close to commercial Pt/C (20%), and the half-wave potential (E1/2) of Z67-900 is 80 mV positive than that of Pt/C in an O2-saturated 0.1 M KOH solution (1600 rpm) with sweep rate of 5 mV·s−1. Moreover, Z67-900 has better methanol resistance. The hierarchical pore structure of Z67-900 facilitates mass transfer, while the Co-Nx sites provide active catalytic centers. This study provides a solid foundation for the rational design of highly efficient ZIF-derived heteroatom-doped catalysts.
]]>Authors: Denis Miroshnichenko Kateryna Shmeltser Maryna Kormer Leonid Bannikov Serhii Nedbailo Mykhailo Miroshnychenko Natalya Mukina Mariia Shved
Given the multi-basin raw material base for coking that has been formed at most industry enterprises, there is an urgent need to optimize the component composition and improve the basic technological methods of coal raw material preparation, taking into account the petrographic characteristics of coal batches. A comprehensive study of the components included in a coke chemical enterprise’s coking raw material base was carried out. The work used standardized methods for studying coal and coal batches’ technological and plastic–viscous properties. The qualitative characteristics of coke were determined using physical–mechanical and thermochemical methods of studying standardized indicators: crushability (M25), abrasion (M10), reactivity (CRI), post-reaction strength (CSR), and specific electrical resistance (ρ). The results were analyzed using the licensed Microsoft Excel computer program. Based on the results of proximate, plastometric, and petrographic analyses of the studied coal samples and data from experimental industrial coking, proposals were made to optimize the component composition, properties of the coal batch, and technology for its preparation for coking. The established inverse dependence of Gibbs free energy (ΔGf,total) on the reaction capacity of coke CRI and its direct reliance on its post-reaction strength CSR confirmed the feasibility of using ΔGf,total as a thermodynamic predictive parameter for optimizing and compiling coal batches that produce less reactive, stronger coke. This made it possible to improve the quality indicators of metallurgical coke. Thus, according to the M25 crushability index, the mechanical strength increased by 0.6%, and the M10 abrasion decreased by 0.4%. Significant improvements in thermochemical properties and an increase in the orderliness of the carbon structure were recorded: the CRI reactivity decreased by 3.1%, the CSR post-reaction strength increased by 8.3%, and the specific resistance decreased by 8.4%.
]]>Authors: Meriem Abid Manuel Martínez-Escandell Joaquín Silvestre-Albero
A high-surface-area activated carbon material (RG) is used as a platform to create highly concentrated NaOH composites. These materials are tested for the removal of H2S under industrially relevant conditions (800 ppm H2S in CO2-, H2O- and O2-containing streams). The experimental results show that the breakthrough performance highly depends on the amount of NaOH incorporated and the experimental conditions used (e.g., relative humidity). The most promising material (RG-NaOH-30) reaches a saturation uptake of up to 800 mgH2S/g at 25 °C and atmospheric pressure. This value is among the most promising results reported in the literature for H2S removal, and it is well above traditional commercial samples. Breakthrough column tests confirm the promoting role of humidity in the reaction mechanism. Analysis of the adsorbents after H2S confirms the formation of well-defined sulfur (Sn) microcrystals as the main reaction product.
]]>Authors: Yating Pan Yunpeng Zhu Donghui Zhang Ning Wei
Effective ablative thermal protection systems are essential for ensuring the structural integrity of hypersonic vehicles subjected to extreme aerothermal loads. However, the microscopic reaction mechanisms at the gas–solid interface, particularly under non-equilibrium high-enthalpy conditions, remain poorly understood. This study employs reactive molecular dynamics (RMD) simulations with the ReaxFF-C/H/O force field to investigate the atomic-scale ablation behavior of a graphene-based knitted graphene structure impacted by atomic oxygen (AO). By systematically varying the AO incident kinetic energy (from 0.1 to 8.0 eV) and incidence angle (from 15° to 90°), we reveal the competing interplay between catalytic recombination and ablation processes. The results show that the catalytic recombination coefficient of oxygen molecules reaches a maximum at 5.0 eV, where surface-mediated O2 formation is most favorable. At higher energies, the reaction pathway shifts toward enhanced CO and CO2 production due to increased carbon atom ejection and surface degradation. Furthermore, as the AO incidence angle increases, the recombination efficiency decreases linearly, while C-C bond breakage intensifies due to stronger vertical energy components. These findings offer new insights into the anisotropic surface response of knitted graphene structures under hyperthermal oxygen exposure and provide valuable guidance for the design and optimization of next-generation thermal protection materials for hypersonic flight.
]]>Authors: Athanasia K. Tolkou
In the past decade, carbon nanostructures have emerged as one of the most rapidly advancing areas of research [...]
]]>Authors: Yilong Li Yi Xie Xuqian Wang Yabo Wang
The treatment of organic phosphate ester (OPE) pollutants in water is a challenging but highly necessary task. In this study, an advanced oxidation process through light activation of peroxymonosulfate (PMS) involving graphene oxide (GO) as a promoter was developed to degrade OPE in water, taking triphenyl phosphate (TPhP) as an example. The developed “Light+PMS+GO” system demonstrated good convenience, high TPhP degradation efficiency, tolerance in a near-neutral pH, satisfactory re-usability, and a low toxicity risk of degradation products. Under the investigated reaction conditions, viz., the full spectrum of a 300 W Xe lamp, PMS of 200 mg L−1, GO of 4 mg L−1, and TPhP of 10 μmol L−1, the “Light+PMS+GO” system achieved nearly 100% TPhP degradation efficiency during a 15 min reaction duration with a 5.81-fold enhancement in the reaction rate constant, compared with the control group without GO. Through quenching experiments and electron paramagnetic resonance studies, singlet oxygen was identified as the main reactive species for TPhP degradation. Further studies implied that GO could accumulate both oxidants and pollutants on the surface, providing additional reaction sites for PMS activation and accelerating electron transfer, which all contributed to the enhancement of TPhP degradation. Finally, the TPhP degradation pathway was proposed and a preliminary toxicity evaluation of degradation intermediates was conducted. The convenience, high removal efficiency, and good re-usability indicates that the developed “Light+PMS+GO” reaction system has great potential for future applications.
]]>Authors: Cliodhna McCann Victoria Gilpin Regan McMath Chris I. R. Gill Karl McCreadie James Uhomoibhi Pagona Papakonstantinou James Davis
Unrefined psyllium husk derived from Plantago ovata constitutes a complex mixture of water-soluble and insoluble polymeric chains that form an interpenetrating network capable of entrapping carbon nanoparticles. While the resulting composite was found to swell in aqueous electrolyte, it exhibited hydrogel-like properties where the electrochemical activity was retained and found to be stable upon repetitive voltammetric cycling. Planar film systems were characterized by electron microscopy, Raman spectroscopy, tensile testing, gravimetric analysis, contact angle and cyclic voltammetry. A key advantage of the composite lies in its ability to be cast in 3D geometric forms such as pyramidal microneedle arrays (700 μm high × 200 μm base × 500 μm pitch) that could serve as viable electrode sensors. In contrast to conventional composite electrode materials that rely on non-aqueous solvents, the psyllium mixture is processed entirely from an aqueous solution. This, along with its plant-based origins and simple processing requirements, provides a versatile matrix for the design of biodegradable electrode structures that can be manufactured from more sustainable sources.
]]>Authors: Alberto Maria Gambelli Federico Rossi Giovanni Gigliotti
The present study deals with hydrate formation with binary gaseous mixtures consisting of carbon dioxide mixed with ethane at varying concentrations. Since the production of hydrates is recognised as a stochastic process and also due to the marked influence that experimental apparatuses often have on the results, the continuous updating of the literature with new experimental data is needed. Hydrates were produced and dissociated in excess water and in unstirred conditions. The dissociation values were collected and tabulated. Each test was plotted and compared with the phase boundary equilibrium conditions of pure ethane and pure carbon dioxide hydrates. The results confirmed the lowering of pressures required for hydrate formation with the increase in ethane concentration in the gas mixture. In detail, the dissociation condition for CO2/C2H6 hydrates was tested within the following thermodynamic ranges: 0.1–13 °C and 11.26–36.75 bar for the 25/75 vol% mixture, 0.1–13 °C and 9.74–35.07 bar for the 50/50 vol% mixture and 7.0–12.9 °C and 17.36–30.05 bar for the 75/25 vol% mixture. When 75 vol% ethane was used, the dissociation of hydrates occurred at conditions corresponding to the phase equilibrium of pure ethane hydrates, denoting that the system reached the most favourable thermodynamic conditions possible despite the presence of 25 vol% CO2.
]]>Authors: Alba N. Ardila Arias Erasmo Arriola-Villaseñor Madelyn Ortiz-Quiceno Lucas Blandón-Naranjo José Alfredo Hernández-Maldonado
The potential of king grass biomass as a precursor for carbon-based materials was evaluated through comprehensive physicochemical characterization. The biomass showed high fixed carbon content, reactive oxygenated groups, and favorable atomic ratios, supporting its suitability for conversion into porous carbon structures. This study focused on the synthesis of graphene-like materials via high-temperature pyrolysis (~1000 °C), employing FeCl3 and potassium ferricyanide (K3[Fe(CN)6]) as catalytic agents. Although FeCl3 is widely studied, it showed limited capacity to promote graphitic ordering. In contrast, K3[Fe(CN)6] exhibited a synergistic effect, combining iron-based catalytic species (Fe, Fe3C) and potassium-derived activating compounds (K2CO3), which significantly enhanced graphitization and porosity. Characterization by Raman spectroscopy, XRD, and SEM confirmed that materials synthesized with K3[Fe(CN)6] presented improved crystallinity, lower defect densities (ID/IG = 0.37–1.11), and distinct 2D bands (I2D/IG = 0.32–0.80), indicating the formation of few-layer graphene domains. The most promising structure was obtained from cellulose treated with alkaline peroxide and deoxygenated prior to pyrolysis with K3[Fe(CN)6], showing properties comparable to commercial graphene. BET analysis revealed surface areas up to 714.50 m2/g. While non-catalyzed samples yielded higher mass, the catalytic approach with K3[Fe(CN)6] demonstrates a sustainable and efficient pathway for producing graphene-like carbon materials from lignocellulosic biomass.
]]>Authors: Xiangjin Liang Jun Lu Yapeng Chen Guangbiao Zhou Zeyan Tao Zhenyu Hu Ying Liu Wanlin Liu Yang Xu Jun Cheng
The column photobioreactor has become the predominant approach for carbon sequestration by microalgae in power plant settings, owing to its capacity for high-density cultivation and efficient light energy utilization. Due to the dense arrangement of the columnar photobioreactor and its height, insufficient light became one of the main factors limiting the carbon sequestration rate of microalgae growth. In this paper, a light resource optimization method of reflective baffle and top diffusing glass was proposed. When the angle of reflective baffle on the north and east walls was 35°, and the angle of reflective baffle on the west and south floors was 0°, the overall light radiation intensity of the reactor array became the largest, reaching up to 916.81 W/m2, which was 14.39% higher than that before the optimization. The replacement of the top glass with diffusing material converted the direct radiation of solar radiation into scattered radiation. When the transmittance was 95% and the haze was 95%, the overall average light radiation intensity of the algal solution reached 830.93 W/m2, which was an increase of 3.7%. Four new exhaust air distribution methods were proposed, in which the three-entrance staggered-arrangement type glasshouse had the lowest algal liquid temperature.
]]>Authors: Arianna D. Rivera Eitan Hershkovitz Panagiotis Panoutsopoulos Manny X. de Jesus Lopez Bradley Simpson Honggyu Kim Rajaram Narayanan Jesse Johnson Kevin S. Jones
Pulsed laser annealing (PLA) was performed on a 0.3 μm thick hydrogenated amorphous carbon (a-C:H) film deposited on silicon substrate by plasma-enhanced chemical vapor deposition (PECVD). The 532 nm, 32 ns PLA ranged in fluence from 0.2 to 0.94 J cm−2. There were no visible signs of film delamination over the entire fluence range for a single pulse. As the fluence increased, graphitization of the amorphous film bulk was observed. However, at the near surface of the film, there was a concomitant increase in sp3 content. The sp3 bonding observed is the result of the formation of a thin diamond-like layer on the surface of the carbon film. Along with increasing laser fluence, the film swelled by 75% up to 0.6 J cm−2. In addition, carbon fiber formation was observed at 0.6 J cm−2, increasing in size and depth up through 0.94 J cm−2. The origin of this transformation may be associated with a rapid outgassing of hydrogen from the amorphous carbon during the PLA step. Additionally, there was a dramatic increase in the visible light absorption of these thin films with increasing laser fluence, despite the films being less than a micron thick. These results suggest that PLA of a-C:H film is a useful method for modifying the surface structure for optical or electrochemical applications without film ablation.
]]>Authors: Teruki Ando Seiya Yokokura Hiroki Waizumi Hironori Suzuki Kenji Kawashima Toshihiro Shimada
Exfoliation of layered materials is an important technique for preparing atomic-layer materials. To provide fundamental mechanistic insights for optimizing this process, we investigated the exfoliation process of nano graphite using molecular dynamics simulations with the ReaxFF force field. The impact of temperature, speed, and angle of removing the top layer has been examined to gain insight into obtaining thin, uniform layers. The bending rigidity of the ReaxFF graphite is temperature-dependent and affects the cleavage behavior. The impact of the Au overlayer, which has recently been utilized to obtain a large area, was also studied, and it was confirmed to be effective in improving repeatability.
]]>Authors: Huihui Wang
Nanozymes, as a new generation of artificial enzymes, have attracted increasing attention in the field of biomedicine due to their multiple enzymatic characteristics, multi-functionality, low cost, and high stability. Among them, carbon dot nanozymes (CDzymes) possess excellent enzymatic-like catalytic activity and biocompatibility and have been developed for various diagnostic and therapeutic studies of diseases. Here, we briefly review the representative research on CDzymes in recent years, including their synthesis, modification, and applications, especially in orthopedic diseases, including osteoarthritis, osteoporosis, osteomyelitis, intervertebral disc degenerative diseases, bone tumors, and bone injury repair and periodontitis. Additionally, we briefly discuss the potential future applications and opportunities and challenges of CDzymes. We hope this review can provide some reference opinions for CDzymes and offer insights for promoting their application strategies in the treatment of orthopedic disease.
]]>Authors: Siddharth Gautam David Cole
Porous materials are characterized by the pore surface area (S) and volume (V) accessible to a confined fluid. For mesoporous materials NMR measurements of diffusion are used to assess the S/V ratio, because at short times, only the diffusivity of molecules in the adsorbed layer is affected by confinement and the fractional population of these molecules is proportional to the S/V ratio. For materials with sub-nanometer pores, this might not be true, as the adsorbed layer can encompass the entire pore volume. Here, using molecular simulations, we explore the role played by S and S/V in determining the dynamical behavior of two carbon-bearing fluids—CO2 and ethane—confined in sub-nanometer pores of silica. S and V in a silicalite model representing a sub-nanometer porous material are varied by selectively blocking a part of the pore network by immobile methane molecules. Three classes of adsorbents were thus obtained with either all of the straight (labeled ‘S-major’) or zigzag channels (‘Z-major’) remaining open or a mix of a fraction of both types of channel blocked, resulting in half of the total pore volume being blocked (‘Half’). While the adsorption layers from opposite surfaces overlap, encompassing the entire pore volume for all pores except the intersections, the diffusion coefficient is still found to be reduced at high S/V, especially for CO2, albeit not so strongly as would be expected in the case of wider pores. This is because of the presence of channel intersections that provide a wider pore space with non-overlapping adsorption layers.
]]>Authors: María Fernanda Amezaga Gonzalez Abdiel Ramirez-Reyes Monica Elvira Mendoza-Duarte Alejandro Vega-Rios Daniel Martinez-Ozuna Claudia A. Rodriguez-Gonzalez Santos-Adriana Martel-Estrada Imelda Olivas-Armendariz
Theranostic agents enable the simultaneous diagnosis and treatment of diseases, and they are particularly useful in fluorescent imaging and cancer therapies. In this study, carbon quantum dots were synthesized via a microwave-assisted method using citric acid and bovine serum albumin (BSA) as precursors. The resulting CQDs exhibited spherical morphology, an average size of 4 nm, and an amorphous graphitic structure. FT-IR characterization revealed the presence of amide bonds and oxygenated functional groups. At the same time, optical analysis showed excitation at 320 nm and emission between 360 and 400 nm, with fluorescent stability maintained for one month. Furthermore, the CQDs demonstrated good thermal stability and photothermal efficiency, reaching temperatures above 41 °C within 15 min under NIR irradiation, with a mass loss of less than 1%. Their stability was evaluated in media with different pH levels, simulating physiological and tumor environments. While their behavior was affected under acidic conditions, their excellent photothermal conversion capacity and overall stability in triple-distilled water positioned them as promising candidates for theranostic applications in cancer, effectively combining diagnostic imaging and thermal therapy.
]]>Authors: Quddus Tushar Muhammed A. Bhuiyan Ziyad Abunada Charles Lemckert Filippo Giustozzi
This study aims to estimate the carbon footprint and relative uncertainties for design components of conventional and geopolymer concrete. All the design components of alkaline-activated geopolymer concrete, such as fly ash, ground granulated blast furnace slag, sodium hydroxide (NaOH), sodium silicate (Na2SiO3), superplasticizer, and others, are assessed to reflect the actual scenarios of the carbon footprint. The conjugate application of the life cycle assessment (LCA) tool SimPro 9.4 and @RISK Monte Carlo simulation justifies the variations in carbon emissions rather than a specific determined value for concrete binders, precursors, and filler materials. A reduction of 43% in carbon emissions has been observed by replacing cement with alkali-activated binders. However, the associative uncertainties of chemical admixtures reveal that even a slight increase may cause significant environmental damage rather than its benefit. Pearson correlations of carbon footprint with three admixtures, namely sodium silicate (r = 0.80), sodium hydroxide (r = 0.52), and superplasticizer (r = 0.19), indicate that the shift from cement to alkaline activation needs additional precaution for excessive use. Therefore, a suitable method of manufacturing chemical activators utilizing renewable energy sources may ensure long-term sustainability.
]]>Authors: Marta Pacheco Adrien Brac de la Perrière Patrícia Moura Carla Silva
Most industrial processes depend on heat, electricity, demineralized water, and chemical inputs, which themselves are produced through energy- and resource-intensive industrial activities. In this work, acetic acid (AA) production from syngas (CO, CO2, and H2) fermentation is explored and compared against a thermochemical fossil benchmark and other thermochemical/biological processes across four main Key Performance Indicators (KPI)—electricity use, heat use, water consumption, and carbon footprint (CF)—for the years 2023 and 2050 in Portugal and France. CF was evaluated through transparent and public inventories for all the processes involved in chemical production and utilities. Spreadsheet-traceable matrices for hotspot identification were also developed. The fossil benchmark, with all the necessary cascade processes, was 0.64 kg CO2-eq/kg AA, 1.53 kWh/kg AA, 22.02 MJ/kg AA, and 1.62 L water/kg AA for the Portuguese 2023 energy mix, with a reduction of 162% of the CO2-eq in the 2050 energy transition context. The results demonstrated that industrial practices would benefit greatly from the transition from fossil to renewable energy and from more sustainable chemical sources. For carbon-intensive sectors like steel or cement, the acetogenic syngas fermentation appears as a scalable bridge technology, converting the flue gas waste stream into marketable products and accelerating the transition towards a circular economy.
]]>Authors: Huan Liu Yuxin Ding Longping Zhou Shirui Xu Bo Liao
Carbon dots (CDs), a class of carbon-based fluorescent nanomaterials, have garnered significant attention due to their tunable optical properties and functional versatility. In this study, we developed a hybrid material by grafting pH- and temperature-responsive copolymers onto CDs via reversible addition-fragmentation chain-transfer (RAFT) polymerization. Triamino-tetraphenylethylene (ATPE) and N-isopropylacrylamide (NIPAM) were copolymerized at varying ratios and covalently linked to CDs, forming a dual-responsive system. Structural characterization using FTIR, 1H NMR, and TEM confirmed the successful grafting of the copolymers onto CDs. The hybrid material exhibited pH-dependent fluorescence changes in acidic aqueous solutions, with emission shifting from 450 nm (attributed to CDs) to 500 nm (aggregation-induced emission, AIE, from ATPE) above a critical pH threshold. Solid films of the hybrid material demonstrated reversible fluorescence quenching under HCl vapor and recovery/enhancement under NH3 vapor, showing excellent fatigue resistance over multiple cycles. Temperature responsiveness was attributed to the thermosensitive poly(NIPAM) segments, with fluorescence intensity increasing above 35 °C due to polymer chain collapse and ATPE aggregation. This work provides a strategy for designing multifunctional hybrid materials with potential applications in recyclable optical pH/temperature sensors.
]]>Authors: Zhe Wang Xiaoping Zhang Shihui Xu Lin Yang Lina Wang Yijing Wang Ahmad Mansoor Wei Sun
In this paper, nanoscale graphene film electrodes were prepared using laser-induced technology, and an in situ electrochemical cell was constructed. The normalized peak areas at 2.82 ppm for the samples without the in situ electrochemical cell and with an in situ electrochemical cell are 4.02 and 4.41, respectively. Tests showed that this in situ electrochemical cell has minimal interference from the nuclear magnetic resonance (NMR) magnetic field, allowing for high-resolution in situ spectra. Using this in situ electrochemical cell and employing in situ electrochemistry combined with NMR techniques, we investigated the oxidation reaction of 0.01 M procarbazine (PCZ) in real-time. We elucidated the following oxidation mechanism for procarbazine: the oxidation of PCZ first generates azo-procarbazine, which then undergoes a double bond shift to hydrazo-procarbazine. hydrazo-procarbazine undergoes hydrolysis to yield benzaldehyde-procarbazine, and then finally oxidizes to produce N-isopropylterephthalic acid. This confirms that the combination of in situ electrochemistry and nuclear magnetic resonance technology provides chemists with an effective tool for in situ studying the reaction mechanisms of drug molecules.
]]>Authors: Igor V. Ershov Anatoly A. Lavrentyev Dmitry L. Romanov Olga M. Holodova
Graphene quantum dots (GQDs) have strong potential in optoelectronics, particularly in LEDs, photodetectors, solar cells, and nanophotonics. While challenges remain in efficiency and scalability, advances in functionalization and hybrid material integration could soon make them commercially viable for next-generation optoelectronic devices. In this work, we assess the stability of various epoxy positions and their impact on the electronic and optical properties of GQDs. The oxygen binding energies and the potential barrier heights at different positions of epoxy groups at the edges and in the core of the GQD were estimated. The effect of possible transformations of epoxy groups into other edge configurations on the structural and optical properties of GQDs was evaluated. The results demonstrate that the functionalization of the GQD surface and edges with an epoxy groups at varying binding sites can result in substantial modification of the electronic structure and absorption properties of the GQDs. The prospects of low temperature annealing for controlling optical properties of epoxidized GQDs were discussed. The present computational work offers atomistic insights that can facilitate the rational design of optoelectronic systems based on GQD materials.
]]>Authors: Md. Muzammal Hoque Biplob Kumar Saha Antonio Scopa Marios Drosos
Due to soil nutrient depletion and rising food demand from an increasing global population, it is essential to find sustainable ways to boost crop yields, improve soil health, and address the environmental issues induced by agriculture. The most appropriate approach is to consider sustainable amendments, such as biochar and its derivatives, which are vital constituents of soil health due to their affordability, low reactivity, large surface area, and reduced carbon footprint. In this context, biochar and its derivatives in farming systems focus on improving soil structure, nutrient holding capacity, microbial activities, and the perpetuation of soil fertility. Despite its benefits, biochar, if it is used in high concentration, can sometimes become highly toxic, causing soil erosion due to reducing surface area, increasing pH levels, and altering soil properties. This review highlights the production methods and sources of feedstocks, emphasizing their important contribution to the soil’s physicochemical and biological properties. Furthermore, it critically evaluates the environmental applications and their impacts, providing data built upon the literature on contaminant removal from soil, economic factors, heavy metal immobilization, carbon sequestration, and climate resilience. This review emphasizes the main challenges and future prospects for biochar use in comparison to modified biochar (MB) to propose the best practices for sustainable farming systems.
]]>Authors: Min-Qi Zhu Xue-Feng Wang
Penta-graphene, a novel two-dimensional carbon allotrope entirely composed of pentagonal carbon rings, has attracted increasing attention due to its unique geometric structure, mechanical robustness, and intrinsic semiconducting nature. In this study, we systematically investigate the adsorption behavior of three typical dissolved gases in transformer oil (CO, C2H2, and C2H4) on penta-graphene using first-principles calculations based on density functional theory. The optimized adsorption configuration, adsorption energy, charge transfer, adsorption distance, band structure, density of states, charge density difference, and desorption time are analyzed to evaluate the sensing capability of penta-graphene. Results reveal that penta-graphene exhibits moderate chemical interactions with CO and C2H2, accompanied by noticeable charge transfer and band structure changes, whereas C2H4 shows weaker physisorption characteristics. The projected density of states analysis further confirms the orbital hybridization between gas molecules and the substrate. Additionally, the desorption time calculations suggest that penta-graphene possesses good sensing and recovery potential, especially under elevated temperatures. These findings indicate that penta-graphene is a promising candidate for use in gas sensing applications related to the monitoring of dissolved gases in transformer oils.
]]>Authors: Yun Zhang Yiwen Guo Kaibo Sun Xiaojing Li Xiuhua Liu Jinhua Zhu Md. Zaved Hossain Khan
Zn-doped carbon dots (Zn@C-210 calcination temperature at 210 °C and Zn@C-260 calcination temperature at 260 °C) were synthesized via an in situ calcination method using zinc citrate complexes as precursors, aiming to investigate the mechanisms of their distinctive fluorescence properties. A range of analytical methods were employed to characterize these nanomaterials. The mechanism study revealed that the coordination structure of Zn-O, formed through zinc doping, can induce a metal–ligand charge-transfer effect, which significantly increases the probability of radiative transitions between the excited and ground states, thereby enhancing the fluorescence intensity. The Zn@C-210 in a solid state and Zn@C-260 in water exhibited approximately 71.50% and 21.1% quantum yields, respectively. Both Zn@C-210 and Zn@C-260 exhibited excitation-independent luminescence, featuring a long fluorescence lifetime of 6.5 μs for Zn@C-210 and 6.2 μs for Zn@C-260. Impressively, zinc-doped CDs displayed exceptional biosafety, showing no acute toxicity even at 1000 mg/kg doses. Zn@C-210 has excellent fluorescence in a solid state, showing promise in anti-photobleaching applications; meanwhile, the dual functionality of Zn@C-260 makes it useful as a folate sensor and cellular imaging probe. These findings not only advance the fundamental understanding of metal-doped carbon dot photophysics but also provide practical guidelines for developing targeted biomedical nanomaterials through rational surface engineering and doping strategies.
]]>Authors: Ming-Liao Tsai An-Ya Lo Jun-Hao Liu Yong-Ming Dai
The inclusion of adsorption thermodynamic analysis and performance benchmarking with existing adsorbents reinforces both the theoretical significance and practical applicability of this study. The modified rubber-derived carbon demonstrated a remarkably high DBT adsorption capacity of 254.45 mg/g. These results establish it as a promising alternative to conventional materials such as commercial activated carbon, zeolites, and even metal–organic framework materials. In addition to confirming the superior performance of the adsorbent, the findings provide a deeper understanding of the DBT adsorption mechanism and offer a solid scientific basis for large-scale fuel desulfurization applications. This research highlights the potential of transforming end-of-life tire waste into value-added functional materials and contributes to the advancement of sustainable and efficient desulfurization technologies. Future work should focus on optimizing surface functionalization and regeneration strategies to further improve long-term adsorption stability and practical deployment.
]]>Authors: Lorenzo Manunza Riccardo Dettori Antonio Cappai Claudio Melis
We investigate the thermal conductivity of graphene Moiré superlattices formed by twisting bilayer graphene (TBG) at small angles, employing approach-to-equilibrium molecular dynamics and lattice dynamics calculations based on the Boltzmann Transport Equation. Our simulations reveal a non-monotonic dependence of the thermal conductivity on the twisting angle, with a local minimum near the first magic angle (θ∼1.1°). This behavior is attributed to the evolution of local stacking configurations—AA, AB, and saddle-point (SP)—across the Moiré superlattice, which strongly affect phonon transport. A detailed analysis of phonon mean free paths (MFP) and mode-resolved thermal conductivity shows that AA stacking suppresses thermal transport, while AB and SP stackings exhibit enhanced conductivity owing to more efficient low-frequency phonon transport. Furthermore, we establish a direct correlation between the thermal conductivity of twisted structures and the relative abundance of stacking domains within the Moiré supercell. Our results demonstrate that even very small changes in twisting angle (<2°) can lead to thermal conductivity variations of over 30%, emphasizing the high tunability of thermal transport in TBG.
]]>Authors: Rafaela Paula Jaqueline Carvalho Antônio Júnior Filipe Fagundes Robson de Lima Evaneide Lima Carlos Oliveira Magno de Oliveira Augusto Bezerra Osania Ferreira Alan Machado
Portland cement production is one of the main global sources of CO2 emissions, driving the search for sustainable solutions to reduce its environmental footprint. This study evaluated the use of biochar derived from sugarcane bagasse as a partial cement replacement in cementitious composites, aiming to investigate its effects on mechanical and microstructural properties. Composites were prepared with 0, 2, and 5 (% w w−1) biochar at two water-to-cement (w/c) ratios: 0.28 and 0.35. It was hypothesized that the porous structure and carbon-rich composition of biochar could enhance the microstructure of the cementitious matrix and contribute to strength development. Characterization of the biochar indicated compliance with the European Biochar Certificate (EBC) standard, high thermal stability, and notable water retention capacity. Mechanical testing revealed that incorporating 5% w w−1 biochar increased compressive strength by up to 48% in the 0.35 w/c formulation compared to the control. Microstructural analyses (SEM/EDS) showed good interaction between the biochar and the cementitious matrix, with the formation of hydration products at the interfaces. The results confirm the potential of sugarcane bagasse biochar as a supplementary cementitious material, promoting more sustainable composites with improved mechanical performance and reduced environmental impact.
]]>Authors: Youcai Meng Tianran Wei Zhiwei Wang Caiyun Wang Junyang Ding Yang Luo Xijun Liu
Electrocatalytic urea synthesis offers great potential for sustainable strategies through CO2 and NO3− reduction reactions. However, the development of high-performance catalysts is often hampered by the complexity of synthetic methodologies and the unresolved nature of C-N coupling pathways. In this study, we present a copper–indium co-doped titanium dioxide (CuIn-TiO2) catalyst that exhibits remarkable efficacy in enhancing the synergistic reduction of CO2 and NO3− to produce urea. The bimetallic CuIn site functions as the primary active site for the C-N coupling reaction, achieving a urea yield rate of 411.8 μg h−1 mgcat−1 with a Faradaic efficiency of 6.7% at −0.8 V versus reversible hydrogen electrode (vs. RHE). A body of experimental and theoretical research has demonstrated that the nanoscale particles enhance the density of active sites and improve the feasibility of reactions on the surface of TiO2. The co-doping of Cu and In has been shown to significantly enhance electronic conductivity, increase the adsorption affinity for *CO2 and *NO3−, and promote the C-N coupling process. The CuIn-TiO2 catalyst has been demonstrated to effectively promote the reduction of NO3− and CO2, as well as accelerate the C-N coupling reaction. This effect is a result of a synergistic interaction among the catalyst’s components.
]]>Authors: Brenda García-Hilerio Lidia Santiago-Silva Pastor T. Matadamas-Ortiz Alejandro Gomez-Sanchez Víctor A. Franco-Luján Heriberto Cruz-Martínez
A density functional theory (DFT) investigation was conducted to study the O2 and CO2 adsorption on very small Pd3−nNin (n = 0–2) clusters supported on N-doped graphene quantum dots (N-GQDs). The study was carried out in two stages. First, the interaction between Pd3−nNin (n = 0–2) clusters and N-GQDs was analyzed. Subsequently, the adsorption behavior of O2 and CO2 molecules on the supported clusters was examined. The calculated interaction energies (Eint) of Pd3−nNin (n = 0–2) clusters on N-GQDs were found to be higher than those on pristine graphene, indicating enhanced cluster stability on N-GQDs. Furthermore, the adsorption energies (Eads) of the O2 molecule on the Pd3 and Pd2Ni clusters deposited on N-GQDs were similar. Meanwhile, the PdNi2 cluster deposited on N-GQDs exhibited the highest Eads (−1.740). The Eads of CO2 on Pd3−nNin (n = 0–2) clusters embedded in N-GQDs were observed to be close to or exceed 1 eV. Upon adsorption of O2 and CO2 on the Pd3−nNin (n = 0–2) clusters supported on N-GQDs, an elongation of the O–O and C–O bond lengths was observed, respectively. This structural change may facilitate the dissociation of these molecules on the supported clusters.
]]>Authors: Carmela Borriello Sabrina Portofino Loredana Tammaro Pierpaolo Iovane Gabriella Rametta Sergio Galvagno
Carbon fiber-reinforced composites (CFRCs) have attracted considerable attention in recent years due to their excellent properties, enabling their use across various sectors. However, their application at high temperatures is limited by the fibers’ lack of oxidation resistance. This study demonstrates a significant advancement in enhancing the oxidation stability performance of carbon fiber-reinforced composites (CFRCs) by developing a silicon carbide (SiC) coating through the ceramization of carbon fibers using silicon (Si) powder. For the first time, this method was applied to recycled carbon fibers from CF thermoplastic composites. The key findings include the successful formation of a uniform SiC coating, with coating thickness increasing with process duration and decreasing at higher temperatures. The treated fibers exhibited substantially improved oxidation resistance, maintaining structural stability above 700 °C—markedly better than that of their uncoated counterparts. Thermogravimetric analysis confirmed that oxidation resistance varied depending on the CF/Si ratio, highlighting this parameter’s critical role. Overall, this study offers a viable pathway to enhance the thermal durability of recycled carbon fibers for high-temperature applications.
]]>Authors: Haibo Ouyang Jiyong Liu Cuiyan Li Tianzhan Shen Jiaqi Liu Mengyao He Yanlei Li Leer Bao
Using low-cost transition-metal chlorides and furfuryl alcohol as raw materials, the (TiZrHfNbTa)C precursor was prepared, and a three-dimensional braided carbon fiber preform (C/C) coated with pyrolytic carbon (PyC) was used as the reinforcing material. A C/C-(TiZrHfNbTa)C composite was successfully fabricated through the precursor impregnation pyrolysis (PIP) process. Under extreme oxyacetylene ablation conditions (2311 °C/60 s), this composite material demonstrated outstanding ablation resistance, with a mass ablation rate as low as 0.67 mg/s and a linear ablation rate of only 20 μm/s. This excellent performance can be attributed to the dense (HfZr)6(TaNb)2O17 oxide layer formed during ablation. This oxide layer not only has an excellent anti-erosion capability but also effectively acts as an oxygen diffusion barrier, thereby significantly suppressing further ablation and oxidation within the matrix. This study provides an innovative strategy for the development of low-cost ultra-high-temperature ceramic precursors and opens up a feasible path for the efficient preparation of C/C-(TiZrHfNbTa)C composites.
]]>Authors: Elnaz Haddadi Alireza Tabarraei
Despite the promising electronic properties of graphene, its lack of an intrinsic bandgap limits its applicability in semiconductor technologies. This has catalyzed the investigation of newly developed two-dimensional carbon materials, including tetragraphene (TG), a quasi-2D semiconducting material featuring a combination of hexagonal and tetragonal rings. This study aims to investigate the mechanical and fracture behaviors of TG using density functional theory (DFT) and molecular dynamics (MD) simulations, studying two distinct atomic configurations of tetragraphene. DFT simulations assess the mechanical properties, while MD simulations explore the fracture dynamics subjected to mixed mode I (opening mode) and mode II (in-plane shear mode) loading. Our analysis focuses on the influence of loading phase angle, crack edge chirality, crack tip configuration, and temperature on crack propagation paths and critical stress intensity factors (SIFs) in TG structures. Our results show that the critical SIF varies by 12.5–21% depending on the crack chirality. Across all loading conditions, increasing the temperature ranging from 300 K to 2000 K reduces the critical SIF by 10–45%, with the largest reductions observed under pure mode I loading. These outcomes offer important insights into the structural integrity of TG and inform its potential integration into flexible nanoelectronic devices, where mechanical reliability is essential.
]]>Authors: Nikolaos Kostoglou Claus Rebholz
Increasing global energy demand and the need for sustainable energy solutions have sparked significant interest in carbon-based materials for energy conversion and storage [...]
]]>Authors: Marianna Guagliano Ana Bahamonde Maurizio Bellotto Cinzia Cristiani Elisabetta Finocchio Antonio Gasco Virginia Muelas-Ramos Karla Jiménez-Bautista Christian de los Ríos Daphne Hermosilla
This study aims to demonstrate the feasibility of the use of chestnut waste as a green and circular material for developing iron-based photocatalysts for non-steroidal anti-inflammatory drug (NSAID) photodegradation. Four Fe-based catalysts and two pristine biochars were obtained upon a pyrolysis process at 500 and 700 °C and fully characterised. Due to the applied synthesis, iron is present in the form of isotropic grains of magnetite (Fe3O4), quite homogeneously dispersed onto the biochar. The textural properties of all the materials are mainly determined by the pyrolytic temperature, which results in macroporous materials at 500 °C and microporous ones at 700 °C. Fe-based catalysts were tested in Diclofenac (DFC) photodegradation. DFC removal was the result of both adsorption and photocatalytic reactions. Despite the good yield in DFC removal (80–100%), the formation of degradation by-products can partially invalidate the good effectiveness of this approach. However, the encouraging results of this study represent a step forward for the possible development of waste-derived biochar-based catalysts for in-field application.
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