Nanomaterials

19 pages, 3259 KB

Open AccessArticle

Nanocellulose-Based Carbon Aerogel Loaded with Composite Metal Oxides and Its Fenton Catalytic Oxidation Degradation of Phenol

by Yunpeng Gao and Jinyang Chen

Nanomaterials 2025, 15(16), 1292; https://doi.org/10.3390/nano15161292 - 21 Aug 2025

Viewed by 481

Abstract

The development of stable and efficient heterogeneous Fenton oxidation for organic pollutant degradation is crucial to avoid iron sludge formation and cumbersome filtration processes. In this study, iron oxide/carbon aerogel was prepared via the sol–gel method, freeze-drying, and high-temperature carbonization using iron nitrate [...] Read more.

The development of stable and efficient heterogeneous Fenton oxidation for organic pollutant degradation is crucial to avoid iron sludge formation and cumbersome filtration processes. In this study, iron oxide/carbon aerogel was prepared via the sol–gel method, freeze-drying, and high-temperature carbonization using iron nitrate heptahydrate, ammonium hydroxide, and cellulose as raw materials, with polyvinylimine serving as the crosslinking agent. To enhance the pH adaptability of the catalyst, copper and cerium elements were introduced. The characterization results demonstrate the iron (III) oxide within the carbon aerogel, achieving phenol degradation efficiency exceeding 95% within 120 min. Meanwhile, the introduction of copper and cerium accelerated the degradation of phenol while maintaining a certain catalytic degradation effect at pH 5-7. In addition, the catalyst exhibited excellent recyclability, retaining 85% of its initial degradation efficiency after five reaction cycles. This work offers a new method for the development of heterogeneous Fenton catalysts. Full article

(This article belongs to the Section Environmental Nanoscience and Nanotechnology)

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16 pages, 2130 KB

Open AccessArticle

Gold Nanoparticles Disrupt Mitochondrial Activity in Hypothalamic POMC Cells: Implications for Energy Homeostasis

by Boglárka Mária Schilling-Tóth, Silvia Ondrašovičová, Eszter Vámos, Balázs Radnai, Daiana Alymbaeva, Tibor Bartha, István Tóth and Dávid Sándor Kiss

Nanomaterials 2025, 15(16), 1291; https://doi.org/10.3390/nano15161291 - 21 Aug 2025

Viewed by 627

Abstract

Background: Gold nanoparticles (AuNPs) have several beneficial properties that make them effective as intracellular drug carriers, and their potential for various diagnostic and therapeutic applications is gaining recognition. Depending on their size and shape, AuNPs can cross the central nervous system (CNS) through [...] Read more.

Background: Gold nanoparticles (AuNPs) have several beneficial properties that make them effective as intracellular drug carriers, and their potential for various diagnostic and therapeutic applications is gaining recognition. Depending on their size and shape, AuNPs can cross the central nervous system (CNS) through the blood–brain barrier (BBB). In the CNS, they can exert a variety of influences on neuronal and glial cells, which can be both supportive—promoting cell health and function—and cytotoxic, potentially leading to cellular damage. The hypothalamus (HT) is the first region where nanoparticles (NPs) interact, as this neuroendocrine center is particularly sensitive to factors in the systemic circulation due to its function and location. This area is affected by systemic factors, including pro-opiomelanocortin (POMC) neurons, which regulate metabolic function and maintain homeostasis. The activity of mitochondria within these cells influences their response to both external factors and the presence of AuNPs, thereby facilitating a complex interplay between nanoparticle interactions and cellular metabolism in this vital brain region. Aims: This study investigates how AuNPs, at different concentrations and exposure times under in vitro conditions, affect the mitochondrial activity of POMC neurons, aiming to provide a comprehensive understanding of the mechanisms in the HT. Methods: The study investigates the effect of varying gold nanoparticle concentrations on the mitochondrial activity of POMC neurons over treatment periods of 1, 15, 24, and 48 h. Mitochondrial activity was measured using a Seahorse XFp Analyzer to provide high-resolution insights. Additionally, mitochondrial functionality was assessed through the detection of reactive oxygen species (ROS) and cell viability. Results: The findings indicated that the effects of gold nanoparticles on mitochondrial activity depend significantly on their concentration and exposure time. Specifically, exposure leads to an increase in early response systems, the citric acid cycle, and proton efflux, ultimately resulting in the inhibition of mitochondrial function and ATP production in POMC cells. This disruption may affect hypothalamic regulation and energy metabolism. Full article

(This article belongs to the Special Issue Exploring the Nanoscale Diversity of Metal Oxides and Their Advanced Electronic and Energy Storage Applications)

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31 pages, 9907 KB

Open AccessArticle

The Synthesis and Photophysical Performance of a Novel Z-Scheme Ho₂FeSbO₇/Bi_0.5Yb_0.5O_1.5 Heterojunction Photocatalyst and the Photocatalytic Degradation of Ciprofloxacin Under Visible Light Irradiation

by Jingfei Luan, Anan Liu, Liang Hao, Boyang Liu and Hengchang Zeng

Nanomaterials 2025, 15(16), 1290; https://doi.org/10.3390/nano15161290 - 21 Aug 2025

Viewed by 487

Abstract

A pyrochlore-type crystal structure photocatalytic nanomaterial, Ho₂FeSbO₇, was successfully synthesized using a hydrothermal method. Additionally, a fluorite-structured Bi_0.5Yb_0.5O_1.5 was prepared via rare earth Yb doping. Finally, a novel Ho₂FeSbO₇/Bi_0.5 [...] Read more.

A pyrochlore-type crystal structure photocatalytic nanomaterial, Ho₂FeSbO₇, was successfully synthesized using a hydrothermal method. Additionally, a fluorite-structured Bi_0.5Yb_0.5O_1.5 was prepared via rare earth Yb doping. Finally, a novel Ho₂FeSbO₇/Bi_0.5Yb_0.5O_1.5 heterojunction photocatalyst (HBHP) was fabricated using a solvothermal method. The crystal structure, surface morphology, and physicochemical properties of the samples were characterized using XRD, a micro-Raman spectrometer, FT-IR, XPS, ultraviolet photoelectron spectroscopy (UPS), TEM, and SEM. The results showed that Ho₂FeSbO₇ possessed a pyrochlore-type cubic crystal structure (space group Fd-3m, No. 227), while Bi_0.5Yb_0.5O_1.5 featured a fluorite-type cubic structure (space group Fm-3m, No. 225). The results of the degradation experiment indicated that when HBHP, Ho₂FeSbO₇, or Bi_0.5Yb_0.5O_1.5 was employed as a photocatalytic nanomaterial, following 140 min of visible light irradiation, the removal efficiency of ciprofloxacin (CIP) reached 99.82%, 86.15%, or 73.86%, respectively. This finding strongly evidenced the remarkable superiority of HBHP in terms of photocatalytic performance. Compared to the individual catalyst Ho₂FeSbO₇, Bi_0.5Yb_0.5O_1.5, or N-doped TiO₂, the removal efficiency of CIP by HBHP was 1.16 times, 1.36 times, or 2.52 times higher than that by Ho₂FeSbO₇, Bi_0.5Yb_0.5O_1.5, or N-doped TiO₂, respectively. The radical trapping experiments indicated that in the CIP degradation process, the hydroxyl radical owned the strongest oxidation ability, followed by the superoxide anion and the photoinduced hole. These studies are of great significance for the degradation of antibiotics and environmental protection. Full article

(This article belongs to the Topic Water Purification and Catalytic Disintegration at the Nanoscale)

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11 pages, 1896 KB

Open AccessArticle

Real-Time Cell Gap Estimation in LC-Filled Devices Using Lightweight Neural Networks for Edge Deployment

by Chi-Yen Huang, You-Lun Zhang, Su-Yu Liao, Wen-Chun Huang, Jiann-Heng Chen, Bo-Chang Dong, Che-Ju Hsu and Chun-Ying Huang

Nanomaterials 2025, 15(16), 1289; https://doi.org/10.3390/nano15161289 - 21 Aug 2025

Viewed by 533

Abstract

Accurate determination of the liquid crystal (LC) cell gap after filling is essential for ensuring device performance in LC-based optical applications. However, the introduction of birefringent materials significantly distorts the transmission spectrum, complicating traditional optical analysis. In this work, we propose a lightweight [...] Read more.

Accurate determination of the liquid crystal (LC) cell gap after filling is essential for ensuring device performance in LC-based optical applications. However, the introduction of birefringent materials significantly distorts the transmission spectrum, complicating traditional optical analysis. In this work, we propose a lightweight machine learning framework using a shallow multilayer perceptron (MLP) to estimate the cell gap directly from the transmission spectrum of filled LC cells. The model was trained on experimentally acquired spectra with peak-to-peak interferometry-derived ground truth values. We systematically evaluated different optimization algorithms, activation functions, and hidden neuron configurations to identify an optimal model setting that balances prediction accuracy and computational simplicity. The best-performing model, using exponential activation with eight hidden units and BFGS optimization, achieved a correlation coefficient near 1 and an RMSE below 0.1 μm across multiple random seeds and training–test splits. The model was successfully deployed on a Raspberry Pi 4, demonstrating real-time inference with low latency, memory usage, and power consumption. These results validate the feasibility of portable, edge-based LC inspection systems for in situ diagnostics and quality control. Full article

(This article belongs to the Special Issue Emerging Trends in Nanostructured Oxide Semiconductors: Synthesis, Characterization, and Applications)

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12 pages, 735 KB

Open AccessArticle

Accurate and Scalable Quantum Hydrodynamic Simulations of Plasmonic Nanostructures Within OFDFT

by Qihong Hu, Runfeng Liu, Xinyu Shan, Xiaoyun Wang, Hong Yang, Heping Zhao and Yonggang Huang

Nanomaterials 2025, 15(16), 1288; https://doi.org/10.3390/nano15161288 - 21 Aug 2025

Viewed by 519

Abstract

Quantum hydrodynamic theory (QHT) provides a computationally efficient alternative to time-dependent density functional theory for simulating plasmonic nanostructures, but its predictive power depends critically on the choice of ground-state electron density and energy functional. To construct ground-state densities, we adopt orbital-free density functional [...] Read more.

Quantum hydrodynamic theory (QHT) provides a computationally efficient alternative to time-dependent density functional theory for simulating plasmonic nanostructures, but its predictive power depends critically on the choice of ground-state electron density and energy functional. To construct ground-state densities, we adopt orbital-free density functional theory and numerically evaluate the effect of different exchange–correlation functionals and kinetic energy functionals. A suitable energy functional to reproduce both the DFT-calculated work function and charge density is identified. In the excited-state part, we adopt this obital-free ground-state density and investigate how variations in the von Weizsäcker kinetic energy fraction within the Laplacian-level functional affect the resonance energy and oscillator strengths. The appropriate functional form is identified, achieving an accuracy comparable to that reported in previous studies. Applied to sodium nanodimers, our approach captures nonlinear density responses at sub-nanometer gaps. This work extends QHT beyond idealized geometries and offers a robust path toward efficient quantum plasmonic modeling. Full article

(This article belongs to the Special Issue New Trends in Plasma Technology for Nanomaterials and Applications)

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17 pages, 827 KB

Open AccessReview

Theoretical Studies of Non-Metal Endohedral Fullerenes

by Zdeněk Slanina, Filip Uhlík, Takeshi Akasaka, Xing Lu and Ludwik Adamowicz

Nanomaterials 2025, 15(16), 1287; https://doi.org/10.3390/nano15161287 - 21 Aug 2025

Viewed by 719

Abstract

This article presents computational studies of non-metal fullerene endohedrals, which are useful for understanding and interpreting experimental results. The encapsulated non-metal species are simple molecules like H₂, N₂, CO, HF, NH₃, H₂O₂, H [...] Read more.

This article presents computational studies of non-metal fullerene endohedrals, which are useful for understanding and interpreting experimental results. The encapsulated non-metal species are simple molecules like H₂, N₂, CO, HF, NH₃, H₂O₂, H₂O, and their aggregates. Predictions of thermodynamic stability and reaction populations are reviewed, based on quantum-chemical and statistical–thermodynamic treatments. As fullerene syntheses are performed at high temperatures, some of the calculations are based on both the encapsulation potential energy and the encapsulation Gibbs energy changes. Full article

(This article belongs to the Special Issue Modeling, Simulation and Optimization of Nanomaterials)

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18 pages, 4612 KB

Open AccessArticle

Nanostructured Higher Manganese Silicide Thermoelectrics Developed by Mechanical Alloying Using High-Purity and Recycled Silicon

by Panagiotis Mangelis, Kostas Georgiou, Panagiotis Savva Ioannou, Savvas Hadjipanteli, Anne-Karin Søiland and Theodora Kyratsi

Nanomaterials 2025, 15(16), 1286; https://doi.org/10.3390/nano15161286 - 21 Aug 2025

Viewed by 700

Abstract

Mechanical alloying (MA) has been proven to be an energy-efficient synthetic route for the development of high-performance thermoelectric (TE) materials. Higher Manganese Silicide (HMS) phases of the general formula Mn(Si_1−xAl_x)_1.75 (0 ≤ x ≤ 0.05) were prepared by [...] Read more.

Mechanical alloying (MA) has been proven to be an energy-efficient synthetic route for the development of high-performance thermoelectric (TE) materials. Higher Manganese Silicide (HMS) phases of the general formula Mn(Si_1−xAl_x)_1.75 (0 ≤ x ≤ 0.05) were prepared by MA implementing a short-time ball-milling process. Powder XRD and SEM analysis were carried out to validate the HMS phases, while small amounts of the secondary phase, MnSi, were also identified, especially for the Al-doped products. Electrical transport properties measurements showed that Al substitution causes an effective hole doping. A remarkable increase in electrical conductivity is observed for the Al-doped phases, while the corresponding reduction in the Seebeck coefficient is indicative of the increase in carrier density. Despite the small percentages of MnSi detected in Al-doped phases, an improvement in TE efficiency is achieved in the series Mn(Si_1−xAl_x)_1.75 (0 ≤ x ≤ 0.05). The 2.5% Al-doped phase exhibits a maximum figure-of-merit (ZT) of 0.43 at 773 K. Moreover, in an effort to utilize recycled silicon byproducts from photovoltaic (PV) manufacturing, Al-doped phases are developed by MA using two types of Si kerf. The two kerf-based products exhibit lower TE efficiencies, due to the increased amounts of the metallic MnSi phase. Full article

(This article belongs to the Section Nanoelectronics, Nanosensors and Devices)

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33 pages, 2609 KB

Open AccessReview

A Comprehensive Approach to Nanotechnology Innovations in Biogas Production: Advancing Efficiency and Sustainability

by Carmen Mateescu, Nicoleta-Oana Nicula and Eduard-Marius Lungulescu

Nanomaterials 2025, 15(16), 1285; https://doi.org/10.3390/nano15161285 - 21 Aug 2025

Viewed by 822

Abstract

The biochemical conversion of biomass waste and organic slurries into clean methane is a valuable strategy for both reducing environmental pollution and advancing alternative energy sources to support energy security. Anaerobic digestion (AD), a mature renewable technology operated in high-performance bioreactors, continues to [...] Read more.

The biochemical conversion of biomass waste and organic slurries into clean methane is a valuable strategy for both reducing environmental pollution and advancing alternative energy sources to support energy security. Anaerobic digestion (AD), a mature renewable technology operated in high-performance bioreactors, continues to attract attention for improvements in energy efficiency, profitability, and long-term sustainability at scale. Recent efforts focus on optimizing biochemical reactions throughout all phases of the anaerobic process while mitigating the production of inhibitory compounds that reduce biodegradation efficiency and, consequently, economic viability. A relatively underexplored but promising strategy involves supplementing fermentation substrates with nanoscale additives to boost biomethane yield. Laboratory-scale studies suggest that nanoparticles (NPs) can enhance process stability, improve biogas yield and quality, and positively influence the value of by-products. This paper presents a comprehensive overview of recent advancements in the application of nanoparticles in catalyzing anaerobic digestion, considering both biochemical and economic perspectives. It evaluates the influence of NPs on bioconversion efficiency at various stages of the process, explores specific metabolic pathways, and addresses challenges associated with recalcitrant biomass. Additionally, currently employed and emerging pre-treatment methods are briefly discussed, highlighting how they affect digestibility and methane production. The study also assesses the potential of various nanocatalysts to enhance anaerobic biodegradation and identifies research gaps that limit the transition from laboratory research to industrial-scale applications. Further investigation is necessary to ensure consistent performance and economic feasibility before widespread adoption can be achieved. Full article

(This article belongs to the Special Issue Unlocking Biomass Energy with Nanomaterials: Catalytic Innovations and Green Transformation)

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3 pages, 147 KB

Open AccessEditorial

Superconductivity and Magnetism in Two-Dimensional and Layered Materials

by Erik Piatti

Nanomaterials 2025, 15(16), 1284; https://doi.org/10.3390/nano15161284 - 21 Aug 2025

Viewed by 498

Abstract

In the last twenty years, two-dimensional and layered materials have emerged as a class of compounds that has attracted unprecedented attention from the scientific community [...] Full article

(This article belongs to the Special Issue Superconductivity and Magnetism in Two-Dimensional and Layered Materials)

28 pages, 4385 KB

Open AccessReview

Sustainable Recycling of Lithium-Ion Battery Cathodes: Life Cycle Assessment, Technologies, and Economic Insights

by Dongjie Pang, Haoyu Wang, Yimin Zeng, Xue Han and Ying Zheng

Nanomaterials 2025, 15(16), 1283; https://doi.org/10.3390/nano15161283 - 20 Aug 2025

Viewed by 1057

Abstract

Rapid growth of electric vehicles has increased demand for lithium-ion batteries (LIBs), raising concerns regarding their end-of-life management. This study comprehensively evaluates the closed-loop recycling of cathode materials from spent LIBs by integrating life cycle assessment (LCA), technoeconomic analysis, and technological comparison. Typical [...] Read more.

Rapid growth of electric vehicles has increased demand for lithium-ion batteries (LIBs), raising concerns regarding their end-of-life management. This study comprehensively evaluates the closed-loop recycling of cathode materials from spent LIBs by integrating life cycle assessment (LCA), technoeconomic analysis, and technological comparison. Typical approaches—including pyrometallurgy, hydrometallurgy, and other processes such as organic acid leaching and in situ reduction roasting—are systematically reviewed. While pyrometallurgy offers scalability, it is hindered by high energy consumption and excessive greenhouse gas emissions. Hydrometallurgy achieves higher metal recovery rates with better environmental performance but requires complex chemical and wastewater management. Emerging methods and regeneration techniques such as co-precipitation and sol–gel synthesis demonstrate potential for high-purity material recovery and circular manufacturing. LCA results confirm that recycling significantly reduces GHG emissions, especially for high-nickel cathode chemistry. However, the environmental benefits are affected by upstream factors such as collection, disassembly, and logistics. Technoeconomic simulations show that profitability is strongly influenced by battery composition, regional cost structures, and collection rates. The study highlights the necessity of harmonized LCA boundaries, process optimization, and supportive policy frameworks to scale environmentally and economically sustainable LIB recycling, ensuring long-term supply security for critical battery materials. Full article

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20 pages, 2915 KB

Open AccessArticle

Green Hydrothermal Synthesis of Mn₃O₄ Nano-Octahedra Using Carménère Grape Pomace Extract and Evaluation of Their Properties for Energy Storage and Electrocatalysis

by Javier Lorca-Ponce, Paula Valenzuela-Bustamante, Paula Cornejo Retamales, Nicolas Nolan Mella, Valentina Cavieres Ríos, María J. Pérez Velez, Andrés M. Ramírez Ramírez and Leslie Diaz Jalaff

Nanomaterials 2025, 15(16), 1282; https://doi.org/10.3390/nano15161282 - 20 Aug 2025

Viewed by 623

Abstract

In this study, a green hydrothermal synthesis method was employed to produce Mn₃O₄ and Mn₃O₄/β-MnO₂ nanostructures using EET-50, an organic extract obtained from a by-product of Carménère wine production. The biomolecules in EET-50 acted as [...] Read more.

In this study, a green hydrothermal synthesis method was employed to produce Mn₃O₄ and Mn₃O₄/β-MnO₂ nanostructures using EET-50, an organic extract obtained from a by-product of Carménère wine production. The biomolecules in EET-50 acted as reducing agents due to their electron-donating functional groups, enabling nanostructure formation without the need for additional chemical reductants. Morphological characterization by SEM revealed that a KMnO₄/EET-50 mass ratio of 3:1 led to the synthesis of nano-octahedra alongside rod-like structures, with shorter reaction times favoring the development of isolated nano-octahedra ranging from 100 nm to 170 nm. Structural analyses by XRD and Raman spectroscopy confirmed the formation of mixed-phase Mn₃O₄/β-MnO₂ and Mn₃O₄ (hausmannite). Electrochemical performance tests demonstrated that Mn₃O₄ nano-octahedra exhibited a superior specific capacitance of 236.27 F/g at 1 mA/g, surpassing the mixed-phase sample by 28.3%, and showed excellent capacitance retention (99.98%) after 100 cycles at 8 mA/g. Additionally, the Mn₃O₄ nano-octahedra exhibited enhanced oxygen evolution reaction performance in alkaline media, with an overpotential of 0.430 V vs. RHE and a Tafel slope of 205 mV/dec. These results underscore the potential of Mn₃O₄ nano-octahedra, synthesized via a green route using grape pomace extract as a reducing agent, offering an environmentally friendly alternative for applications in energy storage and electrocatalysis. Full article

(This article belongs to the Special Issue Advanced Materials: Sustainable Energy Harvesting, Environmental Cleanup and Functional Application)

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12 pages, 2202 KB

Open AccessArticle

Role of Cu in Nanostructural Relationship Between Phase Separation and Deformation-Induced Twinning in Heavily Drawn Non-Equiatomic High-Entropy Alloy Wire

by Sang Hun Shim, Mohsen Saboktakin Rizi, Hossein Minouei and Sun Ig Hong

Nanomaterials 2025, 15(16), 1281; https://doi.org/10.3390/nano15161281 - 20 Aug 2025

Viewed by 569

Abstract

This study investigates the influence of Cu addition on the nanostructural evolution and mechanical performance of a heavily drawn non-equiatomic CoCu_1.71FeMnNi high-entropy alloy (HEA) wire. Through systematic microstructural and compositional analysis, we examine how Cu constituent affects phase separation behavior and [...] Read more.

This study investigates the influence of Cu addition on the nanostructural evolution and mechanical performance of a heavily drawn non-equiatomic CoCu_1.71FeMnNi high-entropy alloy (HEA) wire. Through systematic microstructural and compositional analysis, we examine how Cu constituent affects phase separation behavior and promotes deformation-induced nano-twinning in another phase counterpart. The designed HEA wire exhibits an elongated ultrafine dual face-centered cubic (fcc) lamella structure (i.e., Co-Fe-rich and Cu-rich phases) that emerges through compositional segregation by spontaneous phase separation from the as-cast state. High-resolution electron microscopy reveals the dislocation wall boundaries stabilized by nanoscale phase interfaces. The cold-drawn CoCu_1.71FeMnNi wire features an impressive combination of strength and ductility, as well as an ultimate tensile strength of nearly ~2 GPa with an elongation of over ~6%. These findings highlight the critical role of compositional tuning in controlling the ultrafine lamella structure stabilized by spinodal-like phase decomposition, offering a pathway to engineering high-performance HEA wires for advanced structural applications. Full article

(This article belongs to the Special Issue Advances in Nanostructured Alloys: From Design to Applications)

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12 pages, 3316 KB

Open AccessArticle

Nanoscale Insights into the Mechanical and Tribological Properties of a Nanocomposite Coating

by Chun-Wei Yao and Ian Lian

Nanomaterials 2025, 15(16), 1280; https://doi.org/10.3390/nano15161280 - 19 Aug 2025

Viewed by 609

Abstract

This study investigates the mechanical and tribological behavior of a polydimethylsiloxane (PDMS)–silica nanocomposite coating over the temperature range extending from 24 °C to 120 °C. Nanoindentation tests revealed depth- and temperature-dependent variations in hardness and complex modulus. A time-dependent deformation model accurately captured [...] Read more.

This study investigates the mechanical and tribological behavior of a polydimethylsiloxane (PDMS)–silica nanocomposite coating over the temperature range extending from 24 °C to 120 °C. Nanoindentation tests revealed depth- and temperature-dependent variations in hardness and complex modulus. A time-dependent deformation model accurately captured the viscoelastic and viscoplastic behavior observed during sustained loading, providing predictive insight into the coating’s thermomechanical performance. Tribological evaluation through friction and nanoscratch testing demonstrated a temperature-induced increase in the coefficient of friction. The integration of mechanical and surface metrology and characterization techniques offers a comprehensive understanding of the coating’s behavior under thermal and mechanical stress. These findings support the design of robust nanocomposite coatings with superior functional performance for practical applications requiring enhanced mechanical stability, wear resistance, and thermal tolerance in challenging service environments. Full article

(This article belongs to the Section Nanocomposite Materials)

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29 pages, 17228 KB

Open AccessReview

Biomass-Derived Carbon Dots: Preparation, Properties, and Applications

by Qinfeng Liu, Huan Chen, Ruiyu Mi, Xin Min, Minghao Fang, Xiaowen Wu, Zhaohui Huang and Yangai Liu

Nanomaterials 2025, 15(16), 1279; https://doi.org/10.3390/nano15161279 - 19 Aug 2025

Viewed by 735

Abstract

With the intensification of the global energy crisis, green, low-carbon, and environmentally friendly biomass materials have become the focus of research. Among them, biomass-derived carbon dots (B-CDs), a novel class of sustainable zero-dimensional carbon nanomaterials, attract significant interest due to their environmental friendliness, [...] Read more.

With the intensification of the global energy crisis, green, low-carbon, and environmentally friendly biomass materials have become the focus of research. Among them, biomass-derived carbon dots (B-CDs), a novel class of sustainable zero-dimensional carbon nanomaterials, attract significant interest due to their environmental friendliness, low toxicity, and unique optical properties. Research findings indicate that B-CDs, utilizing biomass materials as carbon sources, demonstrate significant potential in numerous application fields through structural design and photo-functionalization. However, the underlying mechanisms and formation processes of B-CDs remain inadequately elucidated, and systematic summarization still requires further refinement. Therefore, this review systematically summarizes the synthesis methods, precursor structures, formation mechanisms, luminescent properties, and prevailing applications of B-CDs, with a particular emphasis on recent advances in their use for sensing, anti-counterfeiting, bioimaging, and optronics. In addition, the challenges encountered in performance-oriented controllable preparation and large-scale production were also clarified. This comprehensive review provides a theoretical foundation for further research and multidisciplinary applications of B-CDs, thereby contributing to promoting large-scale commercialization and industrial implementation. Full article

(This article belongs to the Special Issue Biomass-Based Functional Nanomaterials: Synthesis and Application)

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16 pages, 25326 KB

Open AccessArticle

Influence of Carbon Quantum Dots on the Orientational Order and Rotational Viscosity of 8CB

by Alfredos Schinas, Stefanos Basim Atata, Dimitris Tsiourvas and Ioannis Lelidis

Nanomaterials 2025, 15(16), 1278; https://doi.org/10.3390/nano15161278 - 19 Aug 2025

Viewed by 516

Abstract

Soft nanocomposites were prepared by dispersing lipophilic carbon quantum dots (CQDs) in the liquid crystal compound 8CB. The quality of the dispersion was evaluated using fluorescence microscopy, while the microstructure of the samples was examined via polarized optical microscopy. We investigated the influence [...] Read more.

Soft nanocomposites were prepared by dispersing lipophilic carbon quantum dots (CQDs) in the liquid crystal compound 8CB. The quality of the dispersion was evaluated using fluorescence microscopy, while the microstructure of the samples was examined via polarized optical microscopy. We investigated the influence of CQDs on the orientational order parameter S as a function of temperature and sample composition by measuring birefringence. Additionally, the Fréedericksz transition threshold, along with the characteristic response and relaxation times, was measured for each sample as a function of temperature and applied voltage amplitude. The extracted rotational viscosity

γ_{1}

exhibits a pretransitional divergence upon cooling toward the smectic-A phase. Its temperature dependence was analyzed using established models from the literature, and the corresponding activation energy was determined. Notably, our analysis suggests that the presence of CQDs alters the power-law dependence of

γ_{1}

on the orientational order parameter S. The influence of CQDs on the elastic constants has been investigated. Full article

(This article belongs to the Section Nanophotonics Materials and Devices)

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14 pages, 1338 KB

Open AccessArticle

Dynamic Susceptibility Contrast Magnetic Resonance Imaging with Carbon-Encapsulated Iron Nanoparticles Navigated to Integrin Alfa V Beta 3 Receptors in Rat Glioma

by Agnieszka Stawarska, Magdalena Bamburowicz-Klimkowska, Wojciech Szeszkowski and Ireneusz Piotr Grudzinski

Nanomaterials 2025, 15(16), 1277; https://doi.org/10.3390/nano15161277 - 18 Aug 2025

Viewed by 550

Abstract

Overexpression of αvβ3 integrin is found in a diverse group of tumors originating from glial cells in the brain, making this transmembrane receptor a promising biomarker for molecular MRI diagnosis. In the study, we conjugated a monoclonal antibody against the β3 subunit (CD61) [...] Read more.

Overexpression of αvβ3 integrin is found in a diverse group of tumors originating from glial cells in the brain, making this transmembrane receptor a promising biomarker for molecular MRI diagnosis. In the study, we conjugated a monoclonal antibody against the β3 subunit (CD61) of the αvβ3 integrin receptor with carbon-encapsulated iron nanoparticles to yield Fe@C-(CH₂)₂-CONH-anti-CD61 bioconjugates that were used in dynamic susceptibility contrast magnetic resonance imaging (DSC-MRI). Wistar rats bearing C6 gliomas were injected as a single bolus (0.5 mL) through the tail vain with a suspension of Fe@C-(CH₂)₂-CONH-anti-CD61 nanoparticles (200 μg mL⁻¹) and the animals were imaged using the T2*-weighted echo planar imaging (T2* EPI) technique. Results showed that intravenously infused nanoparticles targeting αvβ3 integrin receptors provide strong contrast in rat glioma tissues. No such effects were observed in other rat organs, although some post-contrast effects were also noted in the liver and kidney. The study shows that the as-developed nanoparticles decorated with anti-CD61 monoclonal antibodies might be considered as a novel contrast candidate for noninvasive DSC-MRI diagnosis in CD61-positive gliomas. Full article

(This article belongs to the Special Issue Applications of Nanomaterials in Biomedical Imaging and Cancer Therapy: 3rd Edition)

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17 pages, 3914 KB

Open AccessArticle

Green Synthesis of Chitosan-Coated Selenium Nanoparticles for Paclitaxel Delivery

by Mouhaned Y. Al-Darwesh, Maroua Manai, Hammouda Chebbi and Axel Klein

Nanomaterials 2025, 15(16), 1276; https://doi.org/10.3390/nano15161276 - 18 Aug 2025

Viewed by 600

Abstract

Selenium nanoparticles (Se NPs) were synthesized from Na₂SeO₃ using Foeniculum vulgare (fennel) seed extract as mild sustainable reductant, coated with chitosan (Ch), and loaded with Paclitaxel (PTX). The PTX release from the Se@Ch–PTX NPs and their cytotoxicity against MDA-MB-231 breast [...] Read more.

Selenium nanoparticles (Se NPs) were synthesized from Na₂SeO₃ using Foeniculum vulgare (fennel) seed extract as mild sustainable reductant, coated with chitosan (Ch), and loaded with Paclitaxel (PTX). The PTX release from the Se@Ch–PTX NPs and their cytotoxicity against MDA-MB-231 breast cancer cells was studied in view of an application as drug delivery platform. Thermogravimetric analysis (TGA) showed the thermal stability of the NPs up to 300 °C. UV–vis absorption and Fourier transform IR (FT-IR) spectroscopy allowed to trace surface species originating from the F. vulgare extract on the Se NPs, while the surface of the Se@Ch–PTX NPs is characterized from Ch and PTX functionalities. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) showed approximate spherical shaped NPs with sizes ranging from 10 to 40 nm. Zeta potential measurements showed a clear distinction between the −39 mV found the Se NPs and +57 mV for the Ch–PTX coated NPs. The NPs showed good biocompatibility with red blood cells (RBCs) in hemolytic activity assays, exhibiting no hemolytic effects at concentrations ranging from 50 to 400 µg/mL. In vitro release studies showed a sustained and pH-responsive release pattern with a maximum release of about 80% within 22 h for Se@Ch–PTX at pH = 3.5. The Se@Ch–PTX NPs showed high antiproliferative activity against MDA-MB-231 cells with an IC₅₀ value of 12.3 µg/mL compared to about 36 for PTX and 52 µg/mL for the Se NPs. The reactive oxygen species (ROS) activity as studied through DPPH scavenging showed higher values for the Se@Ch–PTX NPs compared to the Se NP. Full article

(This article belongs to the Special Issue Nanomaterials for Biological Applications: Innovative Strategies from Theranostic Approaches to Regenerative Medicine)

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19 pages, 11203 KB

Open AccessArticle

In Situ TEM Observation of Electric Field-Directed Self-Assembly of PbS and PbSe Nanoparticles

by Iryna Zelenina, Harald Böttner, Marcus Schmidt, Yuri Grin and Paul Simon

Nanomaterials 2025, 15(16), 1275; https://doi.org/10.3390/nano15161275 - 18 Aug 2025

Viewed by 511

Abstract

Nano-sized particles of semiconducting lead sulfide and selenide and their 2D thin layers show high potential in applications, such as field-effect transistors, photodetectors, solar cells, and thermoelectric devices. The generation of PbS and PbSe nanobars and nanocubes is evoked by in situ electron [...] Read more.

Nano-sized particles of semiconducting lead sulfide and selenide and their 2D thin layers show high potential in applications, such as field-effect transistors, photodetectors, solar cells, and thermoelectric devices. The generation of PbS and PbSe nanobars and nanocubes is evoked by in situ electron beam treatment, leading to the formation of thin, extended 2D nanolayers. The initial single crystals are decomposed via sublimation of PbS and PbSe in terms of molecular and atomic fragments, which finally condense on the cold substrate to form nanostructures. The fragments in the gas phase were proven using mass spectrometry. In the case of PbS, Pb⁺ and PbS⁺ species could were detected, whereas PbSe disintegrated into Pb⁺, Se₂⁺, and PbSe⁺. The threshold current that initiates fragmentation increases from PbTe via PbSe up to PbS, which is in line with the increasing crystal formation energies. The uniform orientation of independently formed nanoparticles on the macroscopic scale can be explained by an external electric field acting on emerging dipolar nanospecies. The external dipole field originates from the sputtered mother crystal, where the electron flux is initiated; thus, a current arises between the crystal’s hot and cold ends. On the contrary, in small single crystals, due to the lack of sufficient charge carriers, only local material excavation is detected instead of extended depletion and subsequent nanoparticle deposition. This fragmentation process may represent a new preparation route that provides lead chalcogenide nanofilms that are free of contamination or surfactant participation, which are typical drawbacks associated with the application of wet chemical methods. Full article

(This article belongs to the Special Issue Self-Assembled Nanocomposites and Nanostructures for Environmental and Energic Applications)

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51 pages, 5029 KB

Open AccessReview

A Review of Chitosan-Based Electrospun Nanofibers for Food Packaging: From Fabrication to Function and Modeling Insights

by Ji Yang, Haoyu Wang, Lihua Lou and Zhaoxu Meng

Nanomaterials 2025, 15(16), 1274; https://doi.org/10.3390/nano15161274 - 18 Aug 2025

Viewed by 1196

Abstract

Food is fundamental to human survival, health, culture, and well-being. In response to the increasing demand for sustainable food preservation, chitosan (CS)-based electrospun nanofibers have emerged as promising materials due to their biodegradability, biocompatibility, and inherent antimicrobial properties. When combined with other biopolymers [...] Read more.

Food is fundamental to human survival, health, culture, and well-being. In response to the increasing demand for sustainable food preservation, chitosan (CS)-based electrospun nanofibers have emerged as promising materials due to their biodegradability, biocompatibility, and inherent antimicrobial properties. When combined with other biopolymers or bioactive compounds, CS-based nanofibers offer enhanced functionality for applications in food packaging, preservation, and additives. This review summarizes recent advances in the fabrication and performance of CS-polymer and CS-inorganic composite nanofibers, with a focus on their mechanical strength, thermal stability, barrier properties, and antimicrobial efficacy. The use of these nanofibers across a range of food categories—including vegetables, fruits, fresh-cut produce, dairy products, meat, seafood, and nuts—is examined. Beyond experimental approaches, the review also explores the growing role of computational simulations in predicting the mechanical strength, barrier performance, antimicrobial activity, and biodegradability of CS-based nanofibers. Key modeling techniques and simulation tools are summarized. Finally, current challenges and future research directions are discussed, underscoring the potential of CS-based electrospun nanofibers as sustainable and multifunctional solutions for modern food packaging. By integrating experimental advancements with computational insights, this review provides a comprehensive and forward-looking perspective on CS-based electrospun nanofibers for food packaging. Full article

(This article belongs to the Section Theory and Simulation of Nanostructures)

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9 pages, 1352 KB

Open AccessArticle

Ultrasensitive and Selective ZPNRs-H Sensor for Sulfur Gas Molecules Detection

by Shaolong Su, Xiaodong Lv, Jian Gong and Zhi-Qiang Fan

Nanomaterials 2025, 15(16), 1273; https://doi.org/10.3390/nano15161273 - 18 Aug 2025

Viewed by 427

Abstract

The exceptional sensing properties of hydrogen-saturated zigzag phosphorene nanoribbons (ZPNRs-H) for sulfur-containing gases, namely SO₃, SO₂, and H₂S, were investigated using first-principles calculations based on density functional theory. The total energy, adsorption energy, and Mulliken charge transfer [...] Read more.

The exceptional sensing properties of hydrogen-saturated zigzag phosphorene nanoribbons (ZPNRs-H) for sulfur-containing gases, namely SO₃, SO₂, and H₂S, were investigated using first-principles calculations based on density functional theory. The total energy, adsorption energy, and Mulliken charge transfer were assessed to evaluate the adsorption properties of the ZPNRs-H towards these gases. Notably, the ZPNRs-H exhibits physical adsorption for SO₂ and H₂S gas molecules, while demonstrating chemical adsorption for SO₃, characterized by a substantial adsorption energy and pronounced charge transfer. Furthermore, the adsorption of SO₃ significantly modulates the electronic density of states near the Fermi level of ZPNRs-H. The current–voltage (I–V) characteristics unveil a remarkable enhancement in conductivity post-SO₃ adsorption, underscoring the high sensitivity of ZPNRs-H towards SO₃. Our findings provide profound theoretical insights, heralding the potential of ZPNRs-H as a cutting-edge sensor for SO₃ detection. Full article

(This article belongs to the Special Issue Electronic Structure and Transport Properties of Two-Dimensional Materials)

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11 pages, 2034 KB

Open AccessArticle

Te Vacancy Defect Engineering on Fe₃GeTe₂ (001) Basal Planes for Enhanced Oxygen Evolution Reaction: A First-Principles Study

by Yunjie Gao, Wei Su, Yuan Qiu, Dan Shan and Jing Pan

Nanomaterials 2025, 15(16), 1272; https://doi.org/10.3390/nano15161272 - 18 Aug 2025

Viewed by 451

Abstract

Photocatalytic water splitting for hydrogen production is an attractive renewable energy technology, but the oxygen evolution reaction (OER) at the anode is severely constrained by a high overpotential. The two-dimensional vdW ferromagnetic material Fe₃GeTe₂, with its good stability and [...] Read more.

Photocatalytic water splitting for hydrogen production is an attractive renewable energy technology, but the oxygen evolution reaction (OER) at the anode is severely constrained by a high overpotential. The two-dimensional vdW ferromagnetic material Fe₃GeTe₂, with its good stability and excellent metallic conductivity, has potential as an electrocatalyst, but its sluggish surface catalytic reactivity limits its large-scale application. In this work, we adapted DFT calculations to introduce surface Te vacancies to boost OER performance of the Fe₃GeTe₂ (001) surface. Te vacancies induce the charge redistribution of active sites, optimizing the adsorption and desorption of oxygen-containing intermediates. Consequently, the overpotential of the rate-determining step in the OER process of Fe₃GeTe₂ is reduced to 0.34 V, bringing the performance close to that of the benchmark IrO₂ catalyst (0.56 V). Notably, the vacancies’ concentration and configuration significantly modify the electronic structure and thus influence OER activity. This study provides important theoretical evidence for defect engineering in OER catalysis and offers new design strategies for developing efficient and stable electrocatalysts for sustainable energy conversion. Full article

(This article belongs to the Topic Electrocatalytic Advances for Sustainable Energy)

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18 pages, 5626 KB

Open AccessReview

Reactions of Surface-Confined Terminal Alkynes Mediated by Diverse Regulation Strategies

by Yun Wu, Lei Xu, Junxi Li and Chi Zhang

Nanomaterials 2025, 15(16), 1271; https://doi.org/10.3390/nano15161271 - 18 Aug 2025

Viewed by 592

Abstract

Terminal alkynes, characterized by sp-hybridized carbon atoms at the molecular termini, possess high electron density and exceptional chemical reactivity. These properties make them ideal candidates for the synthesis of one-dimensional molecular wires and two-dimensional networks. Advances in nanoscale characterization techniques, such as [...] Read more.

Terminal alkynes, characterized by sp-hybridized carbon atoms at the molecular termini, possess high electron density and exceptional chemical reactivity. These properties make them ideal candidates for the synthesis of one-dimensional molecular wires and two-dimensional networks. Advances in nanoscale characterization techniques, such as scanning tunneling microscopy and atomic force microscopy, have enabled the real-space visualization of molecular assembly and chemical reactions of terminal alkynes and in situ atomic-level manipulations under surface-confined conditions. In addition, through the combination of spectroscopic measurements, physicochemical properties of and information about resulting nanostructures have been achieved. Moreover, density functional theory calculations provide deeper insights into the underlying reaction pathways and mechanisms. From this perspective, this review summarizes recent progress in the assembly and chemical transformations of terminal alkynes on noble metal surfaces. It discusses strategies for structural modulation and reaction selectivity control, including direct incorporation of heteroatoms or functional groups into precursors, the selection of metal surfaces, the introduction of extrinsic components into molecular systems, and atomic-scale manipulations using scanning probes. Full article

(This article belongs to the Section Synthesis, Interfaces and Nanostructures)

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23 pages, 1917 KB

Open AccessReview

Properties of CO₂ Micro-Nanobubbles and Their Significant Applications in Sustainable Development

by Zeyun Zheng, Xingya Wang, Tao Tang, Jun Hu, Xingfei Zhou and Lijuan Zhang

Nanomaterials 2025, 15(16), 1270; https://doi.org/10.3390/nano15161270 - 17 Aug 2025

Viewed by 697

Abstract

As an important part of global carbon neutrality strategies, carbon dioxide (CO₂) capture, utilization, and storage technologies have emerged as critical solutions for reducing carbon emissions. However, conventional CO₂ applications, including food preservation, industrial synthesis, and enhanced oil recovery, face [...] Read more.

As an important part of global carbon neutrality strategies, carbon dioxide (CO₂) capture, utilization, and storage technologies have emerged as critical solutions for reducing carbon emissions. However, conventional CO₂ applications, including food preservation, industrial synthesis, and enhanced oil recovery, face inherent limitations such as suboptimal gas–liquid mass transfer efficiency and inadequate long-term stability. Recent advancements in CO₂ micro-nanobubbles (CO₂ MNBs) have demonstrated remarkable potential across multidisciplinary domains, owing to their distinctive physicochemical characteristics encompassing elevated internal pressure, augmented specific surface area, exceptional stability, etc. In this review, we try to comprehensively explore the unique physicochemical properties of CO₂ MNBs and their emerging applications, including industrial, agricultural, environmental, and energy fields. Furthermore, we provide a prospective analysis of how these minuscule bubbles can emerge as pivotal in future technological innovations. We also offer novel insights and directions for research and applications across related fields. Finally, we engage in predicting their future development trends as a promising technological pathway for advancing carbon neutrality objectives. Full article

(This article belongs to the Special Issue Nano Surface Engineering: 2nd Edition)

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30 pages, 8981 KB

Open AccessArticle

Vibration Transmission Characteristics of Bistable Nonlinear Acoustic Metamaterials Based on Effective Negative Mass

by Ming Gao, Guodong Shang, Jing Guo, Lingfeng Xu and Guiju Fan

Nanomaterials 2025, 15(16), 1269; https://doi.org/10.3390/nano15161269 - 17 Aug 2025

Viewed by 487

Abstract

The growing demand for low-frequency, broadband vibration and noise suppression technologies in next-generation mechanical equipment has become increasingly urgent. Effective negative mass locally resonant structures represent one of the most paradigmatic classes of acoustic metamaterials. Their unique elastic wave bandgaps enable efficient suppression [...] Read more.

The growing demand for low-frequency, broadband vibration and noise suppression technologies in next-generation mechanical equipment has become increasingly urgent. Effective negative mass locally resonant structures represent one of the most paradigmatic classes of acoustic metamaterials. Their unique elastic wave bandgaps enable efficient suppression of low-frequency vibrations, while inherent nonlinear effects provide significant potential for the design and tunability of these bandgaps. To achieve ultra-low-frequency and ultra-broadband vibration attenuation, this study employs Duffing oscillators exhibiting negative-stiffness characteristics as structural elements, establishing a bistable nonlinear acoustic-metamaterial mechanical model. Subsequently, based on the effective negative mass local resonance theory, the perturbation solution for the dispersion curves is derived using the perturbation method. Finally, the effects of mass ratio, stiffness ratio, and nonlinear term on the starting and cutoff frequencies of the bandgap are analyzed, and key geometric parameters influencing the design of ultra-low vibration reduction bandgaps are comprehensively investigated. Subsequently, the influence of external excitation amplitude and the nonlinear term on bandgap formation is analyzed using numerical computation methods. Finally, effective positive mass, negative mass, and zero-mass phenomena within distinct frequency ranges of the bandgap and passband are examined to validate the theoretically derived results. The findings demonstrate that, compared to a positive-stiffness system, the bandgap of the bistable nonlinear acoustic metamaterial incorporating negative-stiffness Duffing oscillators shifts to higher frequencies and widens by a factor of

\sqrt{2}

. The external excitation amplitude F changes the bandgap starting frequency and cutoff frequency. As F increases, the starting frequency rises while the cutoff frequency decreases, resulting in a narrowing of the bandgap width. Within the frequency range bounded by the bandgap starting frequency and cutoff frequency, the region between the resonance frequency and cutoff frequency corresponds to an effective negative mass state, whereas the region between the bandgap starting frequency and resonance frequency exhibits an effective positive mass state. Critically, the bandgap encompasses both effective positive mass and negative mass regions, wherein vibration propagation is suppressed. Concurrently, a zero-mass state emerges within this structure, with its frequency precisely coinciding with the bandgap cutoff frequency. This study provides a theoretical foundation and practical guidelines for designing nonlinear acoustic metamaterials targeting ultra-low-frequency and ultra-broadband vibration and noise mitigation. Full article

(This article belongs to the Special Issue Nonlinear Optics in Low-Dimensional Nanomaterials (Second Edition))

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15 pages, 3913 KB

Open AccessArticle

Diffusion of Alkaline Metals in Two-Dimensional β₁-ScSi₂N₄ and β₂-ScSi₂N₄ Materials: A First-Principles Investigation

by Ying Liu, Han Fu, Wanting Han, Rui Ma, Lihua Yang and Xin Qu

Nanomaterials 2025, 15(16), 1268; https://doi.org/10.3390/nano15161268 - 16 Aug 2025

Viewed by 487

Abstract

The MA₂Z₄ family represents a class of two-dimensional materials renowned for their outstanding mechanical properties and excellent environmental stability. By means of elemental substitution, we designed two novel phases of ScSi₂N₄, namely β₁ and β [...] Read more.

The MA₂Z₄ family represents a class of two-dimensional materials renowned for their outstanding mechanical properties and excellent environmental stability. By means of elemental substitution, we designed two novel phases of ScSi₂N₄, namely β₁ and β₂. Their dynamical, thermal, and mechanical stabilities were thoroughly verified through phonon dispersion analysis, ab initio molecular dynamics (AIMD) simulations, and calculations of mechanical parameters such as Young’s modulus and Poisson’s ratio. Electronic structure analysis using both PBE and HSE06 methods further revealed that both the β₁ and β₂ phases exhibit metallic behavior, highlighting their potential for battery-related applications. Based on these outstanding properties, the climbing image nudged elastic band (CI-NEB) method was employed to investigate the diffusion behavior of Li, Na, and K ions on the material surfaces. Both structures demonstrate extremely low diffusion energy barriers (Li: 0.38 eV, Na: 0.22 eV, K: 0.12 eV), indicating rapid ion migration—especially for K—and excellent rate performance. The lowest barrier for K ions (0.12 eV) suggests the fastest diffusion kinetics, making it particularly suitable for high-power potassium-ion batteries. The significantly lower barrier for Na ions (0.22 eV) compared with Li (0.38 eV) implies that both β₁ and β₂ phases may be more favorable for fast-charging/discharging sodium-ion battery applications. First-principles calculations were applied to determine the open-circuit voltage (OCV) of the battery materials. The β₂ phase exhibits a higher OCV in Li/Na systems, while the β₁ phase shows more prominent voltage for K. The results demonstrate that both phases possess high theoretical capacities and suitable OCVs. Full article

(This article belongs to the Special Issue Two-Dimensional Nanomaterials for High-Performance Transistors and Photodetectors)

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13 pages, 4460 KB

Open AccessArticle

Interstitial Ag⁺ Engineering Enables Superior Resistive Switching in Quasi-2D Halide Perovskites

by Haiyang Qin, Zijia Wang, Qinrao Li, Jianxin Lin, Dongzhu Lu, Yicong Huang, Wenke Gao, Huachuan Wang and Chenghao Bi

Nanomaterials 2025, 15(16), 1267; https://doi.org/10.3390/nano15161267 - 16 Aug 2025

Viewed by 584

Abstract

Halide perovskite-based memristors are promising neuromorphic devices due to their unique ion migration and interface tunability, yet their conduction mechanisms remain unclear, causing stability and performance issues. Here, we engineer interstitial Ag⁺ ions within a quasi-two-dimensional (quasi-2D) halide perovskite ((C₆H [...] Read more.

Halide perovskite-based memristors are promising neuromorphic devices due to their unique ion migration and interface tunability, yet their conduction mechanisms remain unclear, causing stability and performance issues. Here, we engineer interstitial Ag⁺ ions within a quasi-two-dimensional (quasi-2D) halide perovskite ((C₆H₅C₂H₄NH₃)₂Cs_n−1Pb_nI_3n+1) to enhance device stability and controllability. The introduced Ag⁺ ions occupy organic interlayers, forming thermodynamically stable structures and introducing deep-level energy states without structural distortion, which do not act as non-radiative recombination centers, but instead serve as efficient charge trapping centers that stabilize intermediate resistance states and facilitate controlled filament evolution during resistive switching. This modification also leads to enhanced electron transparency near the Fermi level, contributing to improved charge transport dynamics and device performance. Under external electric fields, these Ag⁺ ions act as mobile ionic species, facilitating controlled filament formation and stable resistive switching. The resulting devices demonstrate exceptional performance, featuring an ultrahigh on/off ratio (∼10⁸) and low operating voltages (∼0.31 V), surpassing existing benchmarks. Our findings highlight the dual role of Ag⁺ ions in structural stabilization and conduction modulation, providing a robust approach for high-performance perovskite memristor engineering. Full article

(This article belongs to the Special Issue Quantum Dot Materials and Their Optoelectronic Applications)

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16 pages, 7400 KB

Open AccessArticle

Waterborne Phosphated Alkynediol-Modified Mica Nanosheet/Acrylic Nanocomposite Coatings with Superior Anticorrosive Performance

by Rui Yuan, Zhixing Tang, Mindi Xiao, Minzhao Cai, Xin Yuan and Lin Gu

Nanomaterials 2025, 15(16), 1266; https://doi.org/10.3390/nano15161266 - 16 Aug 2025

Viewed by 464

Abstract

Mica is a naturally layered material recognized for its superior insulation and exceptional barrier properties; however, it is prone to agglomeration, and its compatibility with resin remains to be resolved. In this work, phosphate butynediol ethoxylate (PBEO), synthesized by the reaction of a [...] Read more.

Mica is a naturally layered material recognized for its superior insulation and exceptional barrier properties; however, it is prone to agglomeration, and its compatibility with resin remains to be resolved. In this work, phosphate butynediol ethoxylate (PBEO), synthesized by the reaction of a commercial corrosion inhibitor, butynediol ethoxylate, with phosphorus pentoxide, was employed to modify mica nanosheets (MNs), as evidenced by FTIR, Raman, and XPS. The obtained MN@PBEO demonstrated improved water dispersibility and enhanced compatibility with acrylic latex. EIS measurements revealed that the impedance (|Z|_0.01Hz) for the waterborne acrylic coating with 0.5 wt% MN@PBEO was approximately an order of magnitude greater than that of the pure waterborne acrylic coating after 28 days of immersion in a 3.5 wt% NaCl solution. Additionally, compared to the pure waterborne acrylic coating, the 0.5 wt% MN@PBEO/acrylic nanocomposite coating on Q235 carbon steel exhibited a water diffusion coefficient that was roughly ten times lower, demonstrating substantially enhanced corrosion protection, attributable to its superior barrier properties. Full article

(This article belongs to the Special Issue The Application of 2D Nanomaterials in Enhancing the Performance of Multifunctional Coatings)

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11 pages, 1384 KB

Open AccessArticle

Reverse Design of Three-Band Terahertz Metamaterial Sensor

by Hongyi Ge, Wenyue Cao, Shun Wang, Xiaodi Ji, Yuying Jiang, Xinxin Liu, Yitong Zhou, Yuan Zhang, Qingcheng Sun and Yuxin Wang

Nanomaterials 2025, 15(16), 1265; https://doi.org/10.3390/nano15161265 - 16 Aug 2025

Viewed by 422

Abstract

Terahertz metamaterial devices (TMDs) have demonstrated promising applications in biomass detection, wireless communications, and security inspection. Nevertheless, conventional design methodologies for such devices suffer from extensive iterative optimizations and significant dependence on empirical expertise, substantially prolonging the development cycle. This study proposes a [...] Read more.

Terahertz metamaterial devices (TMDs) have demonstrated promising applications in biomass detection, wireless communications, and security inspection. Nevertheless, conventional design methodologies for such devices suffer from extensive iterative optimizations and significant dependence on empirical expertise, substantially prolonging the development cycle. This study proposes a reverse design framework leveraging a deep neural network (DNN) to enable rapid and efficient TMD synthesis, exemplified through a three-band terahertz metamaterial sensor. The developed DNN model achieves high-fidelity predictions (mean squared error = 0.03) and enables rapid inference for structural parameter generation. Experimental validation across four distinct target absorption spectra confirms high consistency between simulated and target responses, with near-identical triple-band resonance characteristics. Benchmarking against traditional CST-based optimization reveals a 36-fold acceleration in design throughput (200-device parameterization reduced from 36 h to 1 h). This work demonstrates a promising strategy for data-driven reverse design of multi-peak terahertz metamaterials, combining computational efficiency with rigorous electromagnetic performance. Full article

(This article belongs to the Collection Nano-Optics and Nano-Optoelectronics: Challenges and Future Trends)

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25 pages, 1218 KB

Open AccessArticle

Enhancing the Selectivity of Nitroso-R-Salt for the Determination of Co(II) in Lithium Bioleaching Recovery of Smartphone Batteries Using a Combinatorial Methodology Approach

by David Ricart, Antonio David Dorado, Mireia Baeza and Conxita Lao-Luque

Nanomaterials 2025, 15(16), 1264; https://doi.org/10.3390/nano15161264 - 16 Aug 2025

Viewed by 434

Abstract

The selectivity of the colorimetric method for Co(II) determination using the nitroso-R-salt (NRS) in samples with complex matrices has been improved. Interferences caused by Cu(II), Fe(II), Fe(III), Mn(II), Al(III) and Ni(II) ions, which were present in the bioleach ate of lithium-ion batteries, have [...] Read more.

The selectivity of the colorimetric method for Co(II) determination using the nitroso-R-salt (NRS) in samples with complex matrices has been improved. Interferences caused by Cu(II), Fe(II), Fe(III), Mn(II), Al(III) and Ni(II) ions, which were present in the bioleach ate of lithium-ion batteries, have been solved through the sequential addition of masking agents: acetate, fluoride, ethylenediaminetetraacetic acid (EDTA), and strong acids (H₂SO₄). The absorbance of the NRS-Co(II) complex was typically measured at 525 nm, but it was also studied at 550 nm due to minimal interferences observed at 550 nm. The sequence of the masking agent’s addition showed a significant influence on the interference effect. The optimal sequence was sample, acetate–acetic acid buffer solution with dissolved fluoride, NRS, EDTA and H₂SO₄. The proposed method demonstrated robust performance at 550 nm, with a relative standard deviation (RSD) around 2%, and good accuracy (RV% around 100%). The limit of detection (LoD) was 0.1 mg L⁻¹ and the limit of quantification (LoQ) was 0.3 mg L⁻¹. The linear range extended up to 15 mg L⁻¹ (R² = 0.998). Real samples analyzed using the optimized method showed no significant differences when compared to results from atomic absorption spectroscopy, confirming its reliability. Full article

(This article belongs to the Section 2D and Carbon Nanomaterials)

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12 pages, 4086 KB

Open AccessArticle

Iron-Only Metasurface Broadband Absorber for Solar Energy Harvesting

by Lejia Wu, Xin Chen and Dawei Zhang

Nanomaterials 2025, 15(16), 1263; https://doi.org/10.3390/nano15161263 - 16 Aug 2025

Viewed by 446

Abstract

We investigated a metasurface broadband absorber composed entirely of iron and featuring a simple bilayer structure: a metallic iron substrate topped with an iron nanodisk-patterned layer. This absorber structure achieved over 90% absorption across the visible spectrum, with an average absorption of 97%. [...] Read more.

We investigated a metasurface broadband absorber composed entirely of iron and featuring a simple bilayer structure: a metallic iron substrate topped with an iron nanodisk-patterned layer. This absorber structure achieved over 90% absorption across the visible spectrum, with an average absorption of 97%. The designed metasurface structure had an aspect ratio of less than 1, which facilitated high-quality sample fabrication. In contrast to precious or rare metals typically utilized in visible broadband metasurface absorbers, this absorber offers a significant cost advantage. Furthermore, it exhibits polarization insensitivity and maintains a stable performance under oblique incidence over a wide angular range, making it suitable for practical applications. Additionally, the high melting point and favorable thermal conductivity of iron satisfy the requirements for solar harvesting and photothermal conversion devices. Therefore, this paper presents a highly efficient, low-cost, easy-to-fabricate, and operationally stable solution that is amenable to large-scale deployment in solar energy-harvesting devices. Full article

(This article belongs to the Special Issue Advanced Nanomaterials for Microwave Absorption and Electromagnetic Interference Shielding)

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