Search Results (409)

The development of high-performance solid-state energy storage devices is constrained by the limited ionic conductivity of gel electrolytes. To address this challenge, an inductively coupled nitrogen plasma (ICP) surface modification strategy was applied to poly(vinyl alcohol)–potassium hydroxide (PVA–KOH) gel electrolytes. The optimal plasma treatment parameters (150 W, 20 s) were identified based on ionic conductivity measurements. Comprehensive characterization confirmed that plasma treatment effectively introduced nitrogen-containing polar functional groups on the gel surface, induced surface nitrogen doping, increased surface roughness, and disrupted the hydrogen bond network. These synergistic microstructural modifications and chemical modifications increased interfacial polarity and facilitated ion transport, resulting in a 26% enhancement in the ionic conductivity compared with the pristine gel. Solid-state supercapacitors fabricated with the optimized gel electrolyte exhibits improved energy density, enhanced rate capability, and reduced interfacial impedance. These findings demonstrate that nitrogen-induced ICP treatment is an effective surface engineering strategy for improving gel electrolyte performance and advancing solid-state supercapacitor technologies. Full article

Willows (genus Salix) are versatile plants with applications in construction, medicine, and biomass fuel in North America. Advances in breeding have improved willow clones for higher yields and pest resistance, but the chemical content and distribution across different plant parts remain poorly understood. This study examined the variation in chemical elements (carbon, hydrogen, nitrogen, sulfur, chlorine, and ash) across six willow clones (India, Jorr, Olof, Otisco, Preble, and Tora) and three tissue types (wood, bark, twigs). We also compared freeze-drying and oven-drying methods to assess their impact on chemical content. Freeze-dried samples generally exhibited higher carbon and hydrogen concentrations than oven-dried samples, with statistically significant differences primarily observed for carbon, while nitrogen showed no overall significant difference between drying methods. Chemical composition varied among clones, although no single clone consistently dominated across all chemical parameters. In contrast, pronounced tissue-type differences were observed: bark had higher nitrogen, carbon, sulfur, chlorine, and ash contents, whereas wood exhibited relatively higher hydrogen concentrations, with twigs showing intermediate values. These findings suggest that accounting for tissue-specific chemical differences can improve the selection and utilization of willow biomass and increase the accuracy of ecological assessments, including carbon storage estimates. The findings of this study indicate that oven-drying should remain in use within the bioenergy sector, whereas freeze-drying ought to become the preferred standard for carbon-accounting protocols. Full article

Hydrogen, as an alternative energy carrier, presents significant prospects for the transition to more environmentally friendly energy solutions. However, its efficient and safe storage remains a challenge, as materials with high adsorbent capacity and long-term storage capability are required. This study focuses on the synthesis and characterization of a composite material comprising carbon fiber and manganese dioxide (MnO₂/CFs), for the purpose of hydrogen storage. Carbon fiber was chosen as the basis for the composition of the composite material due to its large active surface area and its excellent mechanical, thermal, and electrochemical properties. The deposition of MnO₂ on the surface of carbon fibers took place through two different synthetic pathways: electrochemical deposition and chemical synthesis under different conditions. The electrochemical method enabled the production of a greater amount of oxide with optimized structural and chemical properties, whereas the chemical method was simpler but required more time to achieve comparable or lower-capacity performance. Elemental analysis of the electrochemically produced composites showcased an average of 40.5 ± 0.05 wt% Mn presence, which is an indicator of the quantity of MnO₂ on the surface responsible for hydrogen storage, while the chemically produced composites showcased an average of 7.6 ± 0.05 wt% Mn presence. Manganese oxide’s high specific capacity and reversible redox reaction participation make it suitable for hydrogen storage applications. The obtained results of the hydrogenated samples through physicochemical characterization indicated the formation of the MnOOH intermediate. Regarding these findings it may be remarked that carbon fiber/MnO₂ composites are promising candidates for hydrogen storage technologies. Finally, the fabricated carbon fiber/MnO₂ composites were applied successfully as working electrodes for analysis of the [Fe(CN)₆]^3−/4− redox system in aqueous KCl solutions. Full article

Freshwater scarcity is increasing day by day and has already reached a threatening level, especially in remotely populated areas. One of the technological solutions to this rising concern could be the use of the solar-based humidification–dehumidification (SHDH) method for water desalination. This technology is a promising solution but has challenges such as solar intermittency. This challenge can be solved by integrating SHDH with the phase change material as a solar energy storage medium. Therefore, a novel nano-enhanced binary eutectic phase change material (NEPCM) was developed in this project. PCM consisting of 70 wt.% stearic acid (ST) and 30 wt.% suberic acid (SBU) with a varying concentration of silicon carbide (SiC) nanoparticles (NPs) (0.1 to 3 wt.%) was synthesized specifically considering the need of SHDH application. The systematic thermophysical characterization was conducted to investigate their energy storage capacity, thermal durability, and performance consistency over repeated cycles. DSC analysis revealed that the addition of SiC NPs preserved the thermal stability of the NEPCM, while the phase transition temperature remained nearly unchanged with a variation of less than 0.74%. The value of latent heat is inversely related to the nanoparticle concentration, i.e., from 142.75 kJ/kg for the base PCM to 131.24 kJ/kg at 3 wt.% loading. This corresponds to reductions in latent heat ranging between 0.98% and 8.06%. The FTIR measurement confirms that no chemical reactions or no new functional groups were formed. All original functional groups of ST and SBU remained intact, showing that incorporating the SiC NP to the PCM lead to physical interactions (e.g., hydrogen bonding or surface adsorption). The TGA analysis showed that the SiC NPs in the NEPCM act as supporting material, and its nano-doping enhanced the final degradation temperature and thermal stability. There was negligible change in thermal conductivity for nanoparticle loadings of 0.1% and 0.4%; however, it increased progressively by 5.2%, 10.8%, 23.12%, and 25.8% at nanoparticle loadings of 0.7%, 1%, 2%, and 3%, respectively, at 25 °C. Thermal reliability was analyzed through a DSC thermal cycling test which confirmed the suitability of the material for the desired applications. Full article

Alginate is a natural polysaccharide extracted from brown algae and is commonly used as a biomaterial scaffold in tissue engineering. In this study, we performed phenol functionalization of sodium alginate based on chemical modification methods using 1-ethyl-(3-dimethylaminopropyl)carbodiimide/N-hydroxybutanediimide/2-(N-morpholino) ethanesulfonic acid (EDC/NHS/MES) and tyramine. The presence of phenol groups was confirmed by spectrophotometry and Fourier Transform Infrared. We successfully prepared hydrogels using a horseradish peroxidase/hydrogen peroxide (HRP/H₂O₂) enzymatic system as well as an sodium persulfate (SPS)/ruthenium light-crosslinking system. Optimization identified 1 mM ruthenium and 4 mM SPS as the most effective photo crosslinking conditions. At the same time, 1 mM H₂O₂ and 10 U/mL HRP are considered optimal conditions for the enzyme-linked reaction. Rheological measurements monitored the gelation process, revealing that the viscosity, storage modulus, and loss modulus of the material increased by at least one hundredfold after crosslinking. Thixotropy results demonstrated excellent recovery of the material. Texture analysis indicated that the crosslinked material possessed notable strength and toughness, highlighting its potential applications in tissue engineering after 3D bioprinting. Full article

Against the background of global energy transformation and low-carbon development, numerous difficult-to-mine coal resources (e.g., deep, thin coal seams and low-quality coal) remain underdeveloped, leading to potential resource waste. This study systematically summarizes the feasibility of developing these resources via underground coal gasification (UCG) technology, clarifies its basic chemical/physical processes and typical gas supply/gas withdrawal arrangements, and establishes an analytical framework covering resource utilization, gas production quality control, environmental impact, and cost efficiency. Comparative evaluations are conducted among UCG, surface coal gasification (SCG), natural gas conversion, and electrolysis-based hydrogen production. Results show that UCG exhibits significant advantages: wide resource adaptability (recovering over 60% of difficult-to-mine coal resources), better environmental performance than traditional coal mining and SCG (e.g., less surface disturbance, 50% solid waste reduction), and obvious economic benefits (total capital investment without CCS is 65–82% of SCG, and hydrogen production cost ranges from 0.1 to 0.14 USD/m³, significantly lower than SCG’s 0.23–0.27 USD/m³). However, UCG faces challenges, including environmental risks (groundwater pollution by heavy metals, syngas leakage), geological risks (ground subsidence, rock mass strength reduction), and technical bottlenecks (difficult ignition control, unstable large-scale production). Combined with carbon capture and storage (CCS) technology, UCG can reduce carbon emissions, but CCS only mitigates carbon impact rather than reversing it. UCG provides a large-scale, stable, and economical path for the efficient clean development of difficult-to-mine coal resources, contributing to global energy structure transformation and low-carbon development. Full article

The rapid growth of the hydrogen industry, driven by global decarbonization efforts, has intensified the need for safe and large-capacity storage systems. Although hydrogen is one of the most abundant elements on Earth, its storage remains technically challenging due to its chemical reactivity and stringent containment requirements. Previous research has primarily emphasized the material-level behavior of polymer liners, composites, and metal alloys because chemical compatibility plays a critical role in aboveground high-pressure tanks. However, for underground storage systems, long-term structural stability is governed not only by material performance but also by the geo-mechanical behavior of deep rock masses. This study proposes a seismic design approach for Lined Rock Caverns (LRCs), a deep underground storage concept capable of sustaining high internal pressure. The method incorporates ground-induced deformation and evaluates the additional influence of internal pressure on lining behavior. Numerical analyses demonstrate that internal pressure has a significant stabilizing effect on the structural response by reducing ovalization and suppressing nonlinear deformation mechanisms. The results highlight that internal pressure is not a secondary load but a key design parameter that must be integrated into the seismic evaluation of LRC-based hydrogen storage facilities. Full article

Palladium, a non-toxic platinum-group metal, is widely used in catalysis, electronics, hydrogen storage, and chemical industries because of its excellent physical and chemical properties. However, given that the number of palladium-producing countries is limited, recycling is considered essential for ensuring a stable and sustainable global supply. Here, I describe a simple and efficient method for palladium recovery from electronic waste (e-waste) using Enterobacter oligotrophicus CCA6^T. To clarify biomineralization capacity, the role of electron donors in modulating biomineralization capacity was examined. Findings showed that formic acid was the most effective donor, enhancing the relative recovery rate to 44% compared to 23% without electron donors. Transmission electron microscopy analysis revealed palladium particles (1–10 nm) distributed across the cell wall, periplasmic space and cytoplasm, confirming active biomineralization rather than passive biosorption. Moreover, based on a comparison with the biomineralization mechanism of Escherichia coli, the biomineralization mechanism of E. oligotrophicus CCA6^T was estimated . Reaction parameters were then optimized by testing the effects of formic acid concentration, reaction temperature, and reaction pH. Under optimized conditions, the relative recovery rate exceeded 99% within 6 h using 40 mg/L palladium. When this method was applied to a metal dissolution solution prepared from e-waste , a recovery rate of 94% was achieved from trace concentrations (36 µg/L), and palladium loss from bacteria after the palladium recovery test was negligible (<0.01%). Taken together, these results demonstrate that biomineralization using E. oligotrophicus CCA6^T could potentially be applied to the recovery of palladium from e-waste, particularly for trace-level concentrations where conventional methods are ineffective. Full article

This paper develops an optimal dispatch model for an integrated wind–solar hydrogen-to-ammonia system to address the mismatch between renewable-energy fluctuations and chemical production loads. The model incorporates renewable variability, electrolyzer dynamics, hydrogen-storage regulation, and ammonia-synthesis load constraints, and is solved using a multi-time-scale MILP framework. An efficiency-priority power allocation strategy is further introduced to account for performance differences among electrolyzers. Using real wind–solar output data, a 72-h case study compares three operational schemes: the Balanced Scheme, the Steady-State Scheme, and the Following Scheme. The proposed Balanced Scheme reduces renewable curtailment to 2.4%, lowers ammonia load fluctuations relative to the Following Scheme, and decreases electricity consumption per ton of ammonia by 19.4% compared with the Steady-State Scheme. These results demonstrate that the integrated dispatch model and electrolyzer-cluster control strategy enhance system flexibility, energy efficiency, and overall economic performance in renewable-powered ammonia production. Full article

The quest for enhanced energy efficiency is inextricably linked to advancements in energy storage and conversion, with porous metallic glasses (MGs) serving as catalysts that hold significant potential in this area. In this study, we report the preparation of uniform porous structures by aging-assisted ultrasonic vibration (AAUV). The results indicate that ultrasonic treatment effectively enhances the energy state while preserving the amorphous structure of Zr₆₂Cu_15.5Ni_12.5Al₁₀ MGs. The results demonstrate that UV treatment effectively elevates the energy state while maintaining the amorphous structure. Electrochemical tests reveal significantly improved chemical activity after UV treatment, with a reduced corrosion potential and over 200-fold increase in electrochemical surface area after dealloying. The dealloyed UV-treated samples develop uniform porous structures with Cu-enriched zones, exhibiting exceptional catalytic performance in alkaline media (oxygen evolution reaction: 350 mV, hydrogen evolution reaction: 163 mV), comparable to commercial catalysts. This work provides new insights into developing high-performance MGs through energy-state engineering. Full article

Graphitic nanomaterials have emerged as foundational components in nanoscience owing to their exceptional electrical, mechanical, and chemical properties, which can be tuned by controlling dimensionality and structural order. From zero-dimensional (0D) quantum dots, carbon nano-onions, and nanodiamonds to one-dimensional (1D) nanoribbons, two-dimensional (2D) nanowalls, and three-dimensional (3D) graphene foams, these architectures underpin advancements in catalysis, energy storage, sensing, and electronic technologies. Among various synthesis routes, chemical vapor deposition (CVD) provides unmatched versatility, enabling atomic-level control over carbon supply, substrate interactions, and plasma activation to produce well defined graphitic structures directly on functional supports. This review presents a comprehensive, dimension-resolved overview of CVD-derived graphitic nanomaterials, examining how process parameters such as precursor chemistry, temperature, hydrogen etching, and template design govern nucleation, crystallinity, and morphological evolution across 0D to 3D hierarchies. Comparative analyses of Raman, XPS, and XRD data are integrated to relate structural features with growth mechanisms and functional performance. By connecting mechanistic principles across dimensional scales, this review establishes a unified framework for understanding and optimizing CVD synthesis of graphitic nanostructures. It concludes by outlining a path forward for improving how CVD-grown carbon nanomaterials are made, monitored, and integrated into real devices so these can move from lab-scale experiments to practical, scalable technologies. Full article

The article presents a series of studies on a new polymer binder in the form of an aqueous composition of MA-AANa/D in the aspect of its reusability in the casting process and its safe storage in landfills. FT-IR analysis confirmed that microwave radiation induces crosslinking of both the MA-AANa/D binder and the moulding sand containing it. It was found that after simple treatment of the microwave-cured binder, its original binding properties can be restored, as the hydrogen-bond networks formed under microwave irradiation are reversible. The bending strength ($R_g^u$) tests of both fresh and regenerated moulding sands bonded with MA-AANa/D confirmed that the achieved curing degree meets the requirements for mould and core production. In addition, the biodegradability of the MA-AANa/D binder was evaluated using the Zahn-Wellens test. The progressive biodegradation was monitored through chemical oxygen demand (UV-Vis) measurements and the corresponding biodegradation degree (R_t). The results confirmed that MA-AANa/D is fully biodegradable in aqueous environments, as evidenced by an R_t value of 63.5% after 28 days of testing. Full article

Power-to-Gas is the process by which electrical energy is converted into chemical energy in gaseous form. It conventionally involves an electrolysis stage, producing hydrogen (Power-to-Hydrogen) from electricity and water. Because it relies on emerging technologies, the management of reliability, maintenance, and safety of these systems must address specific issues that are not yet well documented. Jupiter 1000 is an industrial demonstrator of Power-to-Gas, commissioned in 2019 by GRTgaz, which became NaTran in 2025. One of the objectives of the project is to demonstrate the feasibility of this type of process and to share initial feedback to support the development of the industrial Power-to-Gas sector. This paper presents the main lessons learned and results from Jupiter 1000 on reliability, maintenance, and safety for Power-to-Hydrogen installations. The experience gained from this demonstrator revealed that reliability is mainly affected by failures in systems such as compression, storage, and auxiliaries rather than in the electrolysers. Maintenance is challenged by limited availability of hydrogen-adapted equipment and skilled personnel, which can result in extended downtimes. Safety requires advanced leak detection, adapted materials, and comprehensive risk analyses, especially for hydrogen-specific hazards. These findings highlight five priorities for the sector: strengthening the industrial supply chain, improving equipment reliability, developing specialized risk management expertise, advancing safety solutions, and continuing R&D on hazardous phenomena and monitoring. Full article

Chlorobenzoic acids (CBAs) are a group of chlorinated persistent environmental pollutants with hard biodegradability, high water solubility, and well-documented carcinogenic and endocrine-disrupting properties. Electrocatalytic hydrodechlorination (ECH) is a highly efficient method under mild conditions without harmful by-products, but the ECH process commonly requires adding precious metal catalysts such as palladium (Pd). To address the economic constraints and more effective utilization of Pd, a palladium/manganese dioxide (Pd/MnO₂) composite catalyst was developed in this study by chemical deposition. This method utilized the excellent electrochemical activity of MnO₂ as a carrier as well as the hydrogen storage and activation capacity of Pd. The test showed the optimal Pd loading was 7.5%, and the removal percent of 2,4-dichlorobenzoic acid (2,4-DCBA), a typical CBA, reached 97.3% using 0.5 g/L of Pd/MnO₂ after 120 min of electrochemical reaction. Under these conditions, the dechlorination percent can also be as high as 89.6%. A higher current density enhanced the dechlorination efficiency but showed the lower current utilization efficiency. In practical applications, current density should be minimized on the premise of compliance with the water treatment requirement. Mechanistic studies showed that MnO₂ synergistically promoted hydrolysis dissociation and hydrogen spillover and facilitated Pd-mediated adsorption of atomic hydrogen (H*) for dehydrogenation of 2,4-DCBA. The presence of MnO₂ can effectively disperse the loaded Pd and reduce the amount of Pd via the above process. The catalyst exhibited excellent stability over multiple cycles, and the 2,4-DCBA removal could still reach more than 80% after the five cycles. This work establishes electrocatalytic strategies for effectively reducing Pd usage and maintaining high removal of typical CBAs to support CBA-related water treatment. Full article