Nanomaterials

35 pages, 1384 KiB

Open AccessArticle

Development of Diopside-Modified Marl-Based Dielectric Composite for Microelectronics Applications

by Nassima Riouchi, Oussama Riouchi, Othmane Lamrani, El Hassan Yahakoub, Mohammed Mansori, Boštjan Genorio, Mitja Kolar, Petranka Petrova, Soufian El Barkany, Mohamed Abou-Salama and Mohamed Loutou

Nanomaterials 2025, 15(9), 668; https://doi.org/10.3390/nano15090668 (registering DOI) - 27 Apr 2025

Abstract

This research explores the modification of marl by the incorporation of diopside (CaMgSi₂O₆) to develop a composite material with improved dielectric properties, while addressing environmental and economic challenges through the use of abundant natural resources. X-ray fluorescence (XRF) analysis [...] Read more.

This research explores the modification of marl by the incorporation of diopside (CaMgSi₂O₆) to develop a composite material with improved dielectric properties, while addressing environmental and economic challenges through the use of abundant natural resources. X-ray fluorescence (XRF) analysis reveals a high silicate content in the raw marl, mainly SiO₂ (68.12%) and Al₂O₃ (12.54%), while laser particle size analysis indicates a homogeneous grain size distribution centered around 100 µm. The composite was synthesized by the solid-state reaction method, achieving good phase homogeneity. X-ray diffraction (XRD) and infrared spectroscopy confirm the incorporation of diopside, while SEM analysis shows a porous morphology with granular aggregates. The modified material has an average particle size of 11.653 µm, optimizing the electrical properties. Impedance spectroscopy demonstrates improved dielectric performance, with accumulated permittivity and reduced losses, which improves energy storage and dissipation. Tests showed the remarkable stability of dielectric properties over a wide frequency range (10 Hz to 10 MHz) and low-temperature dependence. The performance was demonstrated on a single sample with a thickness of 0.63 mm, demonstrating consistent efficiency. These results position the diopside-modified marl as a promising candidate for electrochemical and microelectronic applications. Full article

(This article belongs to the Special Issue Development of Innovative Devices Using New-Emerging Micro and Nano Technologies)

19 pages, 8907 KiB

Open AccessArticle

Preparation of Polylactide/Halloysite-Nanoclay/Polytetrafluoro-Ethylene Composite Foam and Study of Properties and Morphology

by Silla George Raju, Hanieh Kargarzadeh and Andrzej Galeski

Nanomaterials 2025, 15(9), 667; https://doi.org/10.3390/nano15090667 (registering DOI) - 27 Apr 2025

Abstract

Halloysite nanoclay (HNC) and as-polymerized polytetrafluoroethylene powder (PTFE) were introduced into biodegradable polylactic acid (PLA) via a melt mixing technique to enhance its mechanical, rheological properties and foaming ability. The synergetic effects of these fillers on the morphological, mechanical, thermal, and foaming properties [...] Read more.

Halloysite nanoclay (HNC) and as-polymerized polytetrafluoroethylene powder (PTFE) were introduced into biodegradable polylactic acid (PLA) via a melt mixing technique to enhance its mechanical, rheological properties and foaming ability. The synergetic effects of these fillers on the morphological, mechanical, thermal, and foaming properties of PLA were investigated. Results indicated that the tensile properties were improved in comparison to neat PLA. Differential Scanning Calorimetry (DSC) revealed a decrease in PLA crystallization time with increasing filler concentration, indicating a strong nucleating effect on PLA crystallization. Extensional flow tests showed that strain hardening in PLA composites is influenced by fillers, with PTFE particularly exhibiting a more pronounced effect, attributed to nanofibrillation and entanglement during melt processing. The addition of a dual-filler system improved the melt strength and viscosity of PLA, resulting in foams with decreased cell size and increased cell density. Full article

(This article belongs to the Section Nanocomposite Materials)

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11 pages, 2231 KiB

Open AccessArticle

Investigating Floating-Gate Topology Influence on van der Waals Memory Performance

by Hao Zheng, Yusang Qin, Caifang Gao, Junyi Fang, Yifeng Zou, Mengjiao Li and Jianhua Zhang

Nanomaterials 2025, 15(9), 666; https://doi.org/10.3390/nano15090666 (registering DOI) - 27 Apr 2025

Abstract

As a critical storage technology, the material selection and structural design of flash memory devices are pivotal to their storage density and operational characteristics. Although van der Waals materials can potentially take over the scaling roadmap of silicon-based technologies, the scaling mechanisms and [...] Read more.

As a critical storage technology, the material selection and structural design of flash memory devices are pivotal to their storage density and operational characteristics. Although van der Waals materials can potentially take over the scaling roadmap of silicon-based technologies, the scaling mechanisms and optimization principles at low-dimensional scales remain to be systematically unveiled. In this study, we experimentally demonstrated that the floating-gate length can significantly affect the memory window characteristics of memory devices. Experiments involving various floating-gate and tunneling-layer configurations, combined with TCAD simulations, were conducted to reveal the electrostatic coupling behaviors between floating gate and source/drain electrodes during shaping of the charge storage capabilities. Fundamental performance characteristics of the designed memory devices, including a large memory ratio (82.25%), good retention (>50,000 s, 8 states), and considerable endurance characteristics (>2000 cycles), further validate the role of floating-gate topological structures in manipulating low-dimensional memory devices, offering valuable insights to drive the development of next-generation memory technologies. Full article

(This article belongs to the Special Issue Applications of 2D Materials in Nanoelectronics)

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14 pages, 4885 KiB

Open AccessArticle

Monodisperse SiO₂ Spheres: Efficient Synthesis and Applications in Chemical Mechanical Polishing

by Jinlong Ge, Yu Cao, Hui Han, Xiaoqi Jin, Jing Liu, Yuhong Jiao, Qiuqin Wang and Yan Gao

Nanomaterials 2025, 15(9), 665; https://doi.org/10.3390/nano15090665 (registering DOI) - 27 Apr 2025

Abstract

The atomic level polishing of a material surface affects the accuracy of devices and the application of materials. Silica slurries play an important role in chemical mechanical polishing (CMP) by polishing the material surface. In this study, an efficient and controllable Stöber approach [...] Read more.

The atomic level polishing of a material surface affects the accuracy of devices and the application of materials. Silica slurries play an important role in chemical mechanical polishing (CMP) by polishing the material surface. In this study, an efficient and controllable Stöber approach was developed to synthesize uniform monodisperse silica spheres with different cationic surfactants. The obtained silica spheres exhibited a regular shape with a particle size of 50–150 nm and were distributed evenly and narrowly. The highest surface specific area of the silica spheres was approximately 1155.9 m²/g, which was conducive to the polish process. The monodisperse SiO₂ spheres were applied as abrasives in chemical mechanical polishing. The surface micrographs of silicon wafers during the CMP process were studied using atomic force microscopy (AFM). The results demonstrated that the surface roughness Ra values reduced from 1.07 nm to 0.979 nm and from 1.05 nm to 0.933 nm when using a CTAB-SiO₂ microsphere as an abrasive. These results demonstrate the advantages of monodisperse SiO₂ spheres as abrasive materials in chemical mechanical planarization processes. Full article

(This article belongs to the Topic Surface Science of Materials)

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15 pages, 3210 KiB

Open AccessArticle

Electrocatalyst of PdNi Particles on Carbon Black for Hydrogen Oxidation Reaction in Alkaline Membrane Fuel Cell

by Carolina Silva-Carrillo, Edgar Alonso Reynoso-Soto, Ivan Cruz-Reyes, Moisés Israel Salazar-Gastélum, Balter Trujillo-Navarrete, Sergio Pérez-Sicairos, José Roberto Flores-Hernández, Tatiana Romero-Castañón, Francisco Paraguay-Delgado and Rosa María Félix-Navarro

Nanomaterials 2025, 15(9), 664; https://doi.org/10.3390/nano15090664 (registering DOI) - 27 Apr 2025

Abstract

This work reports the synthesis of PdNi bimetallic particles and Pd on Carbon black (Vulcan XC-72) by reverse microemulsion and the chemical reduction of metallic complexes. The physicochemical characterization techniques used for the bimetallic and metallic materials were TGA, STEM, ICP-OES, and XRD. [...] Read more.

This work reports the synthesis of PdNi bimetallic particles and Pd on Carbon black (Vulcan XC-72) by reverse microemulsion and the chemical reduction of metallic complexes. The physicochemical characterization techniques used for the bimetallic and metallic materials were TGA, STEM, ICP-OES, and XRD. Also, the electrocatalysts were studied by electrochemical techniques such as anodic CO stripping and β-NiOOH reduction to elucidate the Pd and Ni surface sites participation in the reactions. The electrocatalysts were evaluated in the anodic reaction in anion-exchange membrane fuel cells (AEMFC) and the hydrogen oxidation reaction (HOR) in alkaline media. The results indicate that PdNi/C electrocatalysts exhibited higher electrocatalytic activity than Pd/C electrocatalysts in both the half-cell test and in the AEMFC, even with the same Pd loading, which is attributed to the bifunctional mechanism that provides OH^- groups in oxophilic sites associated to Ni, that can facilitate the desorption of Hads in the Pd sites for the bimetallic material. Full article

(This article belongs to the Special Issue Advanced Carbon-Based Nanostructures for Energy Storage and Clean Energy Technologies)

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17 pages, 1133 KiB

Open AccessArticle

Near-Infrared to T-Ray Frequency Conversion Using Kagome Photonic Crystal Resonators

by Deepika Tyagi, Vijay Laxmi, Ahsan Irshad, Abida Parveen, Mehboob Alam, Yibin Tian and Zhengbiao Ouyang

Nanomaterials 2025, 15(9), 663; https://doi.org/10.3390/nano15090663 (registering DOI) - 27 Apr 2025

Abstract

Kagome lattices have attracted significant research interest due to their unique interplay of geometry, topology, and material properties. They provide deep insights into strongly correlated electron systems, novel quantum phases, and advanced material designs, making them fundamental in condensed matter physics and material [...] Read more.

Kagome lattices have attracted significant research interest due to their unique interplay of geometry, topology, and material properties. They provide deep insights into strongly correlated electron systems, novel quantum phases, and advanced material designs, making them fundamental in condensed matter physics and material engineering. This work presents an efficient method for terahertz (THz) wave generation across the entire THz spectrum, leveraging high-quality-factor Kagome-shaped silicon photonic crystal resonators. In the proposed simulation-based approach, an infrared (IR) single-frequency wave interacts with an induced resonance mode within the resonator, producing a THz beat frequency. This beat note is then converted into a standalone THz radiation (T-ray) wave using an amplitude demodulator. Simulations confirm the feasibility of our method, demonstrating that a conventional single-frequency wave can induce resonance and generate a stable beat frequency. The proposed technique is highly versatile, extending beyond THz generation to frequency conversion in electronics, optics, and acoustics, among other domains. Its high efficiency, compact design, and broad applicability offer a promising solution to challenges in THz technology. Furthermore, our findings establish a foundation for precise frequency manipulation, unlocking new possibilities in signal processing, sensing, detection, and communication systems. Full article

(This article belongs to the Special Issue 2D Materials and Metamaterials in Photonics and Optoelectronics)

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15 pages, 10381 KiB

Open AccessArticle

Photocatalytic Response of Flash-Lamp-Annealed Titanium Oxide Films Produced by Oblique-Angle Deposition

by Raúl Gago, Slawomir Prucnal, Francisco Javier Palomares, Leopoldo Álvarez-Fraga, Ana Castellanos-Aliaga and David G. Calatayud

Nanomaterials 2025, 15(9), 662; https://doi.org/10.3390/nano15090662 (registering DOI) - 26 Apr 2025

Abstract

We report the photocatalytic (PC) response of titanium oxide (TiO_x) films grown by reactive DC magnetron sputtering under oblique-angle-deposition (OAD) and subjected to post-deposition flash-lamp-annealing (FLA). Under ballistic growth conditions, OAD yields TiO_x films with either compact or inclined columnar [...] Read more.

We report the photocatalytic (PC) response of titanium oxide (TiO_x) films grown by reactive DC magnetron sputtering under oblique-angle-deposition (OAD) and subjected to post-deposition flash-lamp-annealing (FLA). Under ballistic growth conditions, OAD yields TiO_x films with either compact or inclined columnar structure as the deposition incidence angle (α) with respect to the substrate normal varies from zero to grazing. On the one hand, films produced for α ≤ 45° display a compact and opaque structure comprising the formation of nanocrystalline cubic titanium monoxide (c-TiO) phase. On the other hand, films grown at larger α (≥60°) display tilted columns with amorphous structure, yielding highly porous films and an increased transparency for α > 75°. For TiO_x films grown at large α, FLA induces phase transformation to nanocrystalline anatase from the amorphous state. In contrast to as-grown samples, FLA samples display PC activity as assessed by bleaching of methyl orange dye. The best PC performance is attained for an intermediate situation (α = 60–75°) between compact and columnar structures. The obtained photoactivity is discussed in terms of the different microstructures obtained by OAD and posterior phase formation upon FLA. Full article

(This article belongs to the Special Issue Advances and Innovations in Glancing Angle Deposition and Related Nanostructures)

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13 pages, 5903 KiB

Open AccessArticle

Assembled Carbon Nanostructure Prepared by Spray Freeze Drying for Si-Based Anodes

by Wanxiong Zhu, Liewen Guo, Kairan Li, Mengxue Shen, Chang Lu, Zipeng Jiang, Huaihe Song and Ang Li

Nanomaterials 2025, 15(9), 661; https://doi.org/10.3390/nano15090661 (registering DOI) - 26 Apr 2025

Abstract

Silicon-based materials provide a new pathway to break through the energy storage limits of battery systems but their industrialization process is still constrained by inherent diffusion hysteresis and unstable electrode structures. In this work, we propose a novel structural design strategy employing a [...] Read more.

Silicon-based materials provide a new pathway to break through the energy storage limits of battery systems but their industrialization process is still constrained by inherent diffusion hysteresis and unstable electrode structures. In this work, we propose a novel structural design strategy employing a modified spray freeze drying technique to construct multidimensional carbon nanostructures. The continuous morphological transition from carbon nanowires to carbon nanosheets was facilitated by the inducement of ultralow-temperature phase separation and the effect of polymer self-assembly. The unique wrinkled carbon nanosheet encapsulation effectively mitigated the stress concentration induced by the aggregation of silicon nanoparticles, while the open two-dimensional structure buffered the volume changes of silicon. As expected, the SSC-5M composite retained a reversible capacity of 1279 mAh g⁻¹ after 100 cycles at 0.2 C (1 C = 1700 mAh g⁻¹) and exhibited a capacity retention of 677.1 mAh g⁻¹ after 400 cycles at 1 C, demonstrating excellent cycling stability. This study offers a new strategy for the development of silicon-based energy storage devices. Full article

(This article belongs to the Special Issue Nanoscale Carbon Materials for Advanced Energy-Related Applications)

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24 pages, 7274 KiB

Open AccessArticle

Segmental Mobility, Interfacial Polymer, Crystallization and Conductivity Study in Polylactides Filled with Hybrid Lignin-CNT Particles

by Panagiotis A. Klonos, Rafail O. Ioannidis, Andreas Pitsavas, Nikolaos D. Bikiaris, Sofia P. Makri, Stefania Koutsourea, Alexios Grigoropoulos, Ioanna Deligkiozi, Alexandros Zoikis-Karathanasis, Apostolos Kyritsis and Dimitrios N. Bikiaris

Nanomaterials 2025, 15(9), 660; https://doi.org/10.3390/nano15090660 (registering DOI) - 26 Apr 2025

Abstract

A newly developed series of polylactide (PLA)-based composites filled with hybrid lignin–carbon nanotube (CNTs) particles were studied using thermal and dielectric techniques. The low CNT content (up to 3 wt%) aimed to create conductive networks while enhancing particle–polymer adhesion. For comparison, PLA composites [...] Read more.

A newly developed series of polylactide (PLA)-based composites filled with hybrid lignin–carbon nanotube (CNTs) particles were studied using thermal and dielectric techniques. The low CNT content (up to 3 wt%) aimed to create conductive networks while enhancing particle–polymer adhesion. For comparison, PLA composites based on lignin and CNTs were also examined. Although infrared spectroscopy showed no significant interactions, calorimetry and dielectric spectroscopy revealed a rigid interfacial PLA layer exhibiting restricted mobility. The interfacial polymer amount was found to increase monotonically with the particle content. The hybrid-filled PLA composites exhibited electrical conductivity, whereas PLA/Lignin and PLA/CNTs remained insulators. The result was indicative of a synergistic effect between lignin and CNTs, leading to lowering of the percolation threshold to 3 wt%, being almost ideal for sustainable conductive printing inks. Despite the addition of lignin and CNTs at different loadings, the glass transition temperature of PLA (60 °C) decreased slightly (softer composites) by 1–2 K in the composites, while the melting temperature remained stable at ~175 °C, favoring efficient processing. Regarding crystallization, which is typically slow in PLA, the hybrid lignin/CNT particles promoted crystal nucleation without increasing the total crystallizable fraction. Overall, these findings highlight the potential of eco-friendly conductive PLA composites for new-generation applications, such as printed electronics. Full article

(This article belongs to the Special Issue Nanocatalysis for Environmental Protection, Energy, and Green Chemistry, 2nd Edition)

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14 pages, 3714 KiB

Open AccessArticle

Scindapsus Aureus Resistive Random-Access Memory with Synaptic Plasticity and Sound Localization Function

by Lu Wang, Jiachu Xie, Wantao Su, Zhenjie Du and Mingzhu Zhang

Nanomaterials 2025, 15(9), 659; https://doi.org/10.3390/nano15090659 (registering DOI) - 26 Apr 2025

Abstract

This work presents a memristive device based on a composite of Scindapsus aureus (SA) and gold nanoparticles (Au NPs), which exhibits excellent resistive switching characteristics and supports multiple forms of synaptic plasticity such as paired-pulse facilitation (PPF), spike-rate-dependent plasticity (SRDP), and spike-timing-dependent plasticity [...] Read more.

This work presents a memristive device based on a composite of Scindapsus aureus (SA) and gold nanoparticles (Au NPs), which exhibits excellent resistive switching characteristics and supports multiple forms of synaptic plasticity such as paired-pulse facilitation (PPF), spike-rate-dependent plasticity (SRDP), and spike-timing-dependent plasticity (STDP). The device demonstrates reliable retention, reproducibility, and switching stability. The SA:Au NP composite originates from a natural plant source and possesses green, biodegradable, and biocompatible features, highlighting its potential as a sustainable bio-memristive material for neuromorphic systems. Furthermore, the device exhibits sensitivity to the time interval between paired input pulses, simulating the neural response to interaural time differences (ITDs) in the auditory system. Although not a conventional acoustic sensor, its Δt-responsiveness based on synaptic behavior reveals promising potential in neuromorphic auditory perception and perceptual computing applications. This study provides a foundational synaptic unit for future artificial hearing systems capable of spatial sound localization. Full article

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

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12 pages, 2284 KiB

Open AccessArticle

Activated Carbon from Spartina alterniflora and Its N-Doped Material for Li-Ion Battery Anode

by Hong Shang, Xinmeng Hao, Yougui Zhou, Jia Peng, Lihua Guo, Huipeng Li and Bing Sun

Nanomaterials 2025, 15(9), 658; https://doi.org/10.3390/nano15090658 (registering DOI) - 26 Apr 2025

Abstract

The rampant growth of Spartina alterniflora has been wreaking havoc on the coastal ecosystems, leading to a serious environmental challenge in recent years. One potential solution to this issue involves converting Spartina alterniflora into activated carbon, offering a potential remedy for pollution while [...] Read more.

The rampant growth of Spartina alterniflora has been wreaking havoc on the coastal ecosystems, leading to a serious environmental challenge in recent years. One potential solution to this issue involves converting Spartina alterniflora into activated carbon, offering a potential remedy for pollution while creating value in energy storage applications. Herein, through a facile carbonization process with sodium hydroxide activation, we successfully transformed obsolete Spartina alterniflora into a porous carbon material (called SAC) and its nitrogen-doped derivative (denoted as SANC) by using melamine as the nitrogen source in a similar procedure. The amorphous structure of these materials was confirmed to enhance lithium-ion storage and electrolyte permeation, making them ideal for use as anodes in lithium-ion batteries. As a result, both SAC and SANC, derived from Spartina alterniflora, exhibited outstanding electrochemical performance including high capacity (456.7 and 780.8 mA h g⁻¹ for SAC and SANC, respectively, at the current density of 6 mA g⁻¹), excellent rate performance (from 6 to 600 mA g⁻¹) and long-term cycling stability. Notably, compared to SAC, its N-doped derivative SANC showed superior properties in the battery (retaining a reversible capacity of 412.9 mA h g⁻¹ at the current density of 6 mA g⁻¹ even after 600 repeated charge–discharge cycles), demonstrating the significantly positive impact of heteroatom doping. This work not only offers a strategy to mitigate environmental challenges but also demonstrates the potential for converting waste biomass into a valuable resource for energy storage applications. Full article

(This article belongs to the Special Issue Nanostructured Biomass-Based Materials for Energy Storage and Environmental Remediation)

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12 pages, 2468 KiB

Open AccessArticle

Tailoring Co Distribution in PtCo Alloys for Enhanced Oxygen Reduction Reaction Activity and Durability in Fuel Cells

by Jinhee Lee, Miso Kim, Bongho Lee, Jeonghee Jang, Suhwan Lee, Dae Jong You, Juseok Song and Namgee Jung

Nanomaterials 2025, 15(9), 657; https://doi.org/10.3390/nano15090657 (registering DOI) - 26 Apr 2025

Abstract

In polymer electrolyte membrane fuel cells (PEMFCs), substantial efforts have been made to focus on Pt and Pt alloy catalysts to enhance their catalytic performance. However, these catalysts still fail to meet practical requirements and existing PtCo catalysts face durability issues due to [...] Read more.

In polymer electrolyte membrane fuel cells (PEMFCs), substantial efforts have been made to focus on Pt and Pt alloy catalysts to enhance their catalytic performance. However, these catalysts still fail to meet practical requirements and existing PtCo catalysts face durability issues due to structural limitations. In this study, carbon-supported hybrid PtCo alloy catalysts (H-PtCo) with improved activity and durability are synthesized by reducing Co precursors onto pre-formed colloidal Pt nanoparticles. Elemental mapping via transmission electron microscopy reveals that the H-PtCo catalysts exhibit a high concentration of Co atoms near the sub-surface. This Co enrichment results from the conformal deposition of Co atoms onto Pt nanoparticles, followed by high-temperature treatment. Electrochemical characterizations, including linear sweep voltammetry (LSV) and accelerated durability test (ADT), demonstrate that the H-PtCo catalysts outperform conventional PtCo alloys (C-PtCo), synthesized via the co-reduction method of Pt and Co, in terms of oxygen reduction reaction (ORR) activity and stability. Furthermore, single-cell tests reveal that the H-PtCo catalysts significantly enhance both performance and durability compared to C-PtCo and Pt catalysts. These findings emphasize the critical role of Co atom distribution within PtCo nanoparticles in improving catalytic efficiency and long-term stability. Full article

(This article belongs to the Special Issue Design of Nanocatalysts and Electrodes: Application to Fuel Cell and Water Electrolysis (Second Edition))

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9 pages, 1300 KiB

Open AccessPerspective

Revealing the Role of Interfacial Charge Transfer in Mechanoluminescence

by Xinyi Huo, Shaoxin Li, Bing Sun, Zhonglin Wang and Di Wei

Nanomaterials 2025, 15(9), 656; https://doi.org/10.3390/nano15090656 (registering DOI) - 26 Apr 2025

Abstract

Mechanoluminescence (ML) involves light emission induced by mechanical stress, categorized into triboluminescence (TL), piezoluminescence (PL), sonoluminescence (SL), and triboelectrification-induced electroluminescence (TIEL). The most common is TL, in which crystal fracture generates opposing charges that excite surrounding molecules. In PL, applied pressure induces light [...] Read more.

Mechanoluminescence (ML) involves light emission induced by mechanical stress, categorized into triboluminescence (TL), piezoluminescence (PL), sonoluminescence (SL), and triboelectrification-induced electroluminescence (TIEL). The most common is TL, in which crystal fracture generates opposing charges that excite surrounding molecules. In PL, applied pressure induces light emission via charge recombination. SL occurs in gas-saturated liquids under sudden pressure changes. TIEL has gained increasing attention as it operates without the need for asymmetric crystal structures or strain fields. However, conventional ML faces practical limitations due to its dependence on complex structures or strain fields. In contrast, contact-electro-luminescence (CEL) has emerged as a promising alternative, enabling luminol luminescence via charge transfer and reactive oxygen species generation through contact electrification (CE) between inert dielectrics and water. CEL provides a simpler and more versatile approach than traditional ML techniques, underscoring the pivotal role of charge-transfer processes. This perspective highlights the potential of CEL in expanding ML applications across sensing, energy conversion, and environmental monitoring. Full article

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

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12 pages, 1774 KiB

Open AccessArticle

Rapid and Ultrasensitive Short-Chain PFAS (GenX) Detection in Water via Surface-Enhanced Raman Spectroscopy with a Hierarchical Nanofibrous Substrate

by Ali K. Ismail, Shobha Mantripragada, Renzun Zhao, Sherine O. Obare and Lifeng Zhang

Nanomaterials 2025, 15(9), 655; https://doi.org/10.3390/nano15090655 (registering DOI) - 25 Apr 2025

Abstract

GenX, the trade name of hexafluoropropylene oxide dimer acid (HFPO-DA) and its ammonium salt, is a short-chain PFAS that has emerged as a substitute for the legacy PFAS perfluorooctanoic acid (PFOA). However, GenX has turned out to be more toxic than people originally [...] Read more.

GenX, the trade name of hexafluoropropylene oxide dimer acid (HFPO-DA) and its ammonium salt, is a short-chain PFAS that has emerged as a substitute for the legacy PFAS perfluorooctanoic acid (PFOA). However, GenX has turned out to be more toxic than people originally thought. In order to monitor and regulate water quality according to recently issued drinking water standards for GenX, rapid and ultrasensitive detection of GenX is urgently needed. For the first time, this study reports ultrasensitive (as low as 1 part per billion (ppb)) and fast detection (in minutes) of GenX in water via surface-enhanced Raman spectroscopy (SERS) using a hierarchical nanofibrous SERS substrate, which was prepared by assembling ~60 nm Ag nanoparticles on electrospun nylon-6 nanofibers through a “hot start” method. The findings in this research highlight the potential of the engineered hierarchical nanofibrous SERS substrate for enhanced detection of short-chain PFASs in water, contributing to the improvement of environmental monitoring and management strategies for PFASs. Full article

(This article belongs to the Special Issue Nanoscale Materials for Detection and Remediation of Water Pollutants)

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30 pages, 10147 KiB

Open AccessReview

Boron Phosphide: A Comprehensive Overview of Structures, Properties, Synthesis, and Functional Applications

by Qilong Wu, Jiamin Wu, Maoping Xu, Yi Liu, Qian Tian, Chuang Hou and Guoan Tai

Nanomaterials 2025, 15(9), 654; https://doi.org/10.3390/nano15090654 - 25 Apr 2025

Abstract

Boron phosphide (BP), an emerging III–V semiconductor, has garnered significant interest because of its exceptional structural stability, wide bandgap, high thermal conductivity, and tunable electronic properties. This review provides a comprehensive analysis of BP, commencing with its distinctive structural characteristics and proceeding with [...] Read more.

Boron phosphide (BP), an emerging III–V semiconductor, has garnered significant interest because of its exceptional structural stability, wide bandgap, high thermal conductivity, and tunable electronic properties. This review provides a comprehensive analysis of BP, commencing with its distinctive structural characteristics and proceeding with a detailed examination of its exceptional physicochemical properties. Recent progress in BP synthesis is critically examined, with a focus on key fabrication strategies such as chemical vapor deposition, high-pressure co-crystal melting, and molten salt methods. These approaches have enabled the controlled growth of high-quality BP nanostructures, including bulk crystals, nanoparticles, nanowires, and thin films. Furthermore, the review highlights the broad application spectrum of BP, spanning photodetectors, sensors, thermal management, energy conversion, and storage. Despite these advances, precise control over the growth, morphology, and phase purity of BP’s low-dimensional structures remains a critical challenge. Addressing these limitations requires innovative strategies in defect engineering, heterostructure design, and scalable manufacturing techniques. This review concludes by outlining future research directions that are essential for unlocking BP’s potential in next-generation electronics, sustainable energy technologies, and multifunctional materials. Full article

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

21 pages, 3317 KiB

Open AccessArticle

Comparative Property Analysis of One-by-One Rib Lingerie Fabrics Fabricated from Modal Fibers and Microfibers

by Antoneta Tomljenović and Juro Živičnjak

Nanomaterials 2025, 15(9), 653; https://doi.org/10.3390/nano15090653 - 25 Apr 2025

Abstract

Although the applicability of modal fibers and microfibers for the production of lingerie knitwear is confirmed by commercial use, their share in the total consumption of man-made cellulosic fibers is very low. Their applicability in the fabrication of one-by-one rib weft-knitted fabrics, as [...] Read more.

Although the applicability of modal fibers and microfibers for the production of lingerie knitwear is confirmed by commercial use, their share in the total consumption of man-made cellulosic fibers is very low. Their applicability in the fabrication of one-by-one rib weft-knitted fabrics, as well as comparative analyses of the influence of differently spun modal and modal-micro yarns on physical, usage, esthetic and wearing comfort properties have not been sufficiently investigated. In this study, a comparative analysis of innovative rib knitted fabrics made of regular–fine modal fibers (1.3 dtex) and 1.0 dtex microfibers is therefore carried out to determine their properties at different relaxation stages. For this purpose, two lines of one-by-one rib fabrics were fabricated from ring-, air-jet- and open-end rotor-spun modal and modal-micro yarns in the same way. The results showed that rib lingerie fabrics fabricated from modal microfibers are lighter and thinner, have a higher voluminosity and moisture absorption capacity, and consequently have slightly lower porosity, breathability and abrasion resistance than fabrics made from modal regular–fine fibers, as well as comparable dimensional stability, tensile strength and pilling properties, but mainly after a wet relaxation treatment. Full article

(This article belongs to the Special Issue Advances in Micro and Nanofiber: Fabrication, Properties and Applications)

16 pages, 16663 KiB

Open AccessArticle

Mechanical Response of FeNiCrCoAl High-Entropy Alloys at the Nanoscale: Predictions from Molecular Dynamics

by Ernesto Amaro, Joaly Delgado-Alvarez, Jairo Andrés Martínez-Uribe and Sergio Mejía-Rosales

Nanomaterials 2025, 15(9), 652; https://doi.org/10.3390/nano15090652 - 25 Apr 2025

Abstract

The mechanical response of high-entropy alloys (HEAs), specifically the FeNiCrCoAl HEA, was studied at both bulk and nanoparticle scales using molecular dynamics simulations. These simulations were performed using the LAMMPS software with an Embedded Atom Method (EAM) potential. The results show that Bulk [...] Read more.

The mechanical response of high-entropy alloys (HEAs), specifically the FeNiCrCoAl HEA, was studied at both bulk and nanoparticle scales using molecular dynamics simulations. These simulations were performed using the LAMMPS software with an Embedded Atom Method (EAM) potential. The results show that Bulk HEAs exhibited enhanced hardening and plasticity, while in nanoparticles, distinct deformation patterns were observed, including nanotwin formation, V-shaped stacking fault planes, and intermittent dislocation activity due to free surface effects. The crystallographic orientation with respect to the compression significantly affected the deformation mechanisms, with the [100] direction favoring progressive hardening, while the [110] and [111] directions exhibited different stacking fault and dislocation dynamics. A detailed analysis using von Mises stress and dislocation analysis provided insights into the effects of scale on mechanical properties. Full article

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

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18 pages, 1255 KiB

Open AccessSystematic Review

Evaluation of Factors Influencing Fluoride Release from Dental Nanocomposite Materials: A Systematic Review

by Alicja Morawska-Wilk, Julia Kensy, Sylwia Kiryk, Agnieszka Kotela, Jan Kiryk, Mateusz Michalak, Natalia Grychowska, Magdalena Fast, Jacek Matys and Maciej Dobrzyński

Nanomaterials 2025, 15(9), 651; https://doi.org/10.3390/nano15090651 - 25 Apr 2025

Abstract

This systematic review aims to evaluate factors influencing fluoride release from dental nanocomposite materials. A comprehensive database search was conducted in February 2025 using PubMed, Web of Science, and Scopus. The search terms “fluoride release AND nanocomposites” were applied following PRISMA guidelines. Out [...] Read more.

This systematic review aims to evaluate factors influencing fluoride release from dental nanocomposite materials. A comprehensive database search was conducted in February 2025 using PubMed, Web of Science, and Scopus. The search terms “fluoride release AND nanocomposites” were applied following PRISMA guidelines. Out of 336 initially identified articles, 17 studies met the inclusion criteria and were selected for analysis. Seventeen studies confirmed that fluoride-releasing nanocomposites are effective, with fluoride ion release influenced by material composition, nanofiller type, and storage conditions. Studies showed that acidic environments (pH 4–5.5) significantly enhanced fluoride release, particularly in materials containing nano-CaF₂ or fluoridated hydroxyapatite, which responded to pH changes. Quantitative comparisons revealed that daily fluoride release values ranged from <0.1 μg/cm²/day in commercial composites to greater than 6500 μg/cm²/day in BT-based nanocomposites and up to 416,667 μg/cm²/day in modified GICs. Additionally, some composites exhibited fluoride recharging capabilities, with materials incorporating pyromellitic glycerol dimethacrylate (PMGDM) and ethoxylated bisphenol A dimethacrylate (EBPADMA) demonstrating prolonged fluoride and calcium ion release after recharge exposure, rather than the highest initial values. Despite releasing lower fluoride levels than conventional GIC and RMGI materials, fluoride-releasing nanocomposites demonstrate significant anti-caries potential and clinical applicability, with some formulations supporting periodontal regeneration and caries prevention around orthodontic brackets. However, the lack of consistency in study protocols—including differences in storage media, sample geometry, and measurement methods—limits direct comparison of outcomes. Therefore, the most critical direction for future research is the development of standardized testing protocols to ensure reliable, comparable results across material groups. Full article

(This article belongs to the Section Nanocomposite Materials)

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18 pages, 2635 KiB

Open AccessArticle

Rescaling Flow Curves of Protein-Stabilized Emulsions

by Santiago F. Velandia, Philippe Marchal, Véronique Sadtler, Cécile Lemaitre, Daniel Bonn and Thibault Roques-Carmes

Nanomaterials 2025, 15(9), 650; https://doi.org/10.3390/nano15090650 - 25 Apr 2025

Abstract

In this study, we investigate the flow behavior of oil-in-water Pickering emulsions stabilized with bovine serum albumin (BSA). Through the use of a phase transition analogy and scaling parameters previously applied to surfactant-stabilized emulsions, we successfully describe the flow behavior, suggesting remarkable similarity [...] Read more.

In this study, we investigate the flow behavior of oil-in-water Pickering emulsions stabilized with bovine serum albumin (BSA). Through the use of a phase transition analogy and scaling parameters previously applied to surfactant-stabilized emulsions, we successfully describe the flow behavior, suggesting remarkable similarity in the rheology of these emulsion categories. Additionally, we explore the possibility of extending this modeling framework to the oscillatory mode. Above the jamming fraction, the scaled data in the oscillatory regime present a similar trend as the rotational rheology curves. However, upon closer examination of the scaling conditions, it becomes evident that the rescaling does not accurately describe the behavior of

|G^{*}|

. Despite this, our findings shed light on the universality of scaling parameters and provide valuable insights into the rheological behavior of these complex fluids. Full article

(This article belongs to the Special Issue Characterization and Properties of Nanostructures in Liquids and Liquid/Liquid Interfaces)

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12 pages, 6777 KiB

Open AccessArticle

NaOH as an Aqueous Electrolyte to Improve the Performance of Electric Double-Layer Capacitors—A Molecular Dynamics Study

by Lifeng Ni and Jin Yu

Nanomaterials 2025, 15(9), 649; https://doi.org/10.3390/nano15090649 - 25 Apr 2025

Abstract

Aqueous electrolytes are widely used in supercapacitors (SCs) because of their high stability, wide voltage window, and safety features at elevated temperatures. Among alkaline electrolytes, KOH is most commonly used, and other electrolytes are less addressed. In this work, we meticulously investigated the [...] Read more.

Aqueous electrolytes are widely used in supercapacitors (SCs) because of their high stability, wide voltage window, and safety features at elevated temperatures. Among alkaline electrolytes, KOH is most commonly used, and other electrolytes are less addressed. In this work, we meticulously investigated the diffusion behavior of Na⁺ and K⁺ in aqueous electrolytes going through hierarchical porous activated carbon materials by employing molecular dynamic simulations. Our results show that the diffusion coefficient of NaOH is much larger than that of KOH under different concentrations, electric fields, and temperatures. We attributed this to the radical of ions going through the mesopores with layered structures. The advantage of high diffusion and low cost of NaOH electrolyte suggests that it could be a potential candidate to improve the performance of SCs. Full article

(This article belongs to the Special Issue Application of Nanoporous Carbon in Energy)

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16 pages, 1431 KiB

Open AccessReview

Electrolyte Effect on Electrocatalytic CO₂ Reduction

by Jiandong Zhang, Ziliang Zhang, Tianye Chen, Jiayi Zhang and Yu Zhang

Nanomaterials 2025, 15(9), 648; https://doi.org/10.3390/nano15090648 - 25 Apr 2025

Abstract

Electrocatalytic CO₂ reduction reaction shows great potential for converting CO₂ into high-value chemicals and fuels at normal temperature and pressure, combating climate change and achieving carbon neutrality goals. However, the complex reaction pathways involve the transfer of multiple electrons and protons, [...] Read more.

Electrocatalytic CO₂ reduction reaction shows great potential for converting CO₂ into high-value chemicals and fuels at normal temperature and pressure, combating climate change and achieving carbon neutrality goals. However, the complex reaction pathways involve the transfer of multiple electrons and protons, resulting in poor product selectivity, and the existence of competitive hydrogen evolution reactions further increases the associated difficulties. This review illustrates the research progress on the micro mechanism of electrocatalytic CO₂ reduction reaction in the electrolyte environment in recent years. The reaction pathways of the products, pH effects, cation effects and anion effects were systematically summarized. Additionally, further challenges and difficulties were also pointed out. Thus, this review provides a theoretical basis and future research direction for improving the efficiency and selectivity of electrocatalytic CO₂ reduction reaction. Full article

(This article belongs to the Section Energy and Catalysis)

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18 pages, 2308 KiB

Open AccessArticle

High-Speed All-Optical Encoder and Comparator at 120 Gb/s Using a Carrier Reservoir Semiconductor Optical Amplifier

by Amer Kotb and Kyriakos E. Zoiros

Nanomaterials 2025, 15(9), 647; https://doi.org/10.3390/nano15090647 - 24 Apr 2025

Abstract

All-optical encoders and comparators are essential components for high-speed optical computing, enabling ultra-fast data processing with minimal latency and low power consumption. This paper presents a numerical analysis of an all-optical encoder and comparator architecture operating at 120 Gb/s, based on carrier reservoir [...] Read more.

All-optical encoders and comparators are essential components for high-speed optical computing, enabling ultra-fast data processing with minimal latency and low power consumption. This paper presents a numerical analysis of an all-optical encoder and comparator architecture operating at 120 Gb/s, based on carrier reservoir semiconductor optical amplifier-assisted Mach–Zehnder interferometers (CR-SOA-MZIs). Building upon our previous work on all-optical arithmetic circuits, this study extends the application of CR-SOA-MZI structures to implement five key logic operations between two input signals (A and B):

\bar{A} B

,

A \bar{B}

, AB (AND),

\bar{A} \bar{B}

(NOR), and AB +

\bar{A} \bar{B}

(XNOR). The performance of these logic gates is evaluated using the quality factor (QF), yielding values of 17.56, 17.04, 19.05, 10.95, and 8.33, respectively. We investigate the impact of critical design parameters on the accuracy and stability of the logic outputs, confirming the feasibility of high-speed operation with robust signal integrity. These results support the viability of CR-SOA-MZI-based configurations for future all-optical logic circuits, offering promising potential for advanced optical computing and next-generation photonic information processing systems. Full article

(This article belongs to the Special Issue Advanced Nanomaterials for Semiconductor Photonics and Their Applications in AI and Sensing)

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21 pages, 17026 KiB

Open AccessReview

On-Surface Ullmann-Type Coupling Reactions of Aryl Halide Precursors with Multiple Substituted Sites

by Qiwei Liu, Yuhong Gao and Chi Zhang

Nanomaterials 2025, 15(9), 646; https://doi.org/10.3390/nano15090646 - 24 Apr 2025

Abstract

The fabrication of low-dimensional nanostructures through on-surface synthesis has emerged as a promising strategy for developing high-precision electronic devices. Among various reactions, Ullmann-type coupling (with carbon–halogen bond activation) stands out in this field as a prevalent methodology due to its straightforward activation process, [...] Read more.

The fabrication of low-dimensional nanostructures through on-surface synthesis has emerged as a promising strategy for developing high-precision electronic devices. Among various reactions, Ullmann-type coupling (with carbon–halogen bond activation) stands out in this field as a prevalent methodology due to its straightforward activation process, highly programmable characteristics, and remarkable synthetic efficiency. To date, on-surface Ullmann-type coupling reactions of aryl halide precursors have been extensively studied with the assistance of in situ characterization techniques. The resulting carbon-based nanostructures exhibit high structural diversity and significant potential for applications in molecular electronics. This review categorizes recent progress in the precise preparation of carbon-based nanostructures based on molecular precursors with distinct halogen substituted sites, including para-, meta-, and ortho-sites, peri- and bay-regions, and their combination. In addition, systematic analysis and comparative discussion of their respective characteristics is also provided. Full article

(This article belongs to the Special Issue Functionalized Nanostructures on Surfaces and at Interfaces)

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15 pages, 8949 KiB

Open AccessArticle

Ellipsometric Surface Oxidation Model of ALD-Grown Vanadium Oxide Mixed-Valence System

by Xiaojie Sun, Shuguang Wang, Qingyuan Cai, Jingze Liu, Changhai Li, Ertao Hu, Jing Li, Songyou Wang, Yuxiang Zheng, Liangyao Chen and Youngpak Lee

Nanomaterials 2025, 15(9), 645; https://doi.org/10.3390/nano15090645 - 24 Apr 2025

Abstract

Vanadium and oxygen form a complex system of vanadium oxides with multiple phases and mixed valency, increasing the difficulty of characterization. In this work, amorphous vanadium oxide thin films with mixed valence states were fabricated by atomic layer deposition, and then post-annealing was [...] Read more.

Vanadium and oxygen form a complex system of vanadium oxides with multiple phases and mixed valency, increasing the difficulty of characterization. In this work, amorphous vanadium oxide thin films with mixed valence states were fabricated by atomic layer deposition, and then post-annealing was conducted for crystalline films. For the surface analysis of this mixed-valence system, X-ray photoelectron spectroscopy (XPS) and Auger electron spectroscopy (AES) were employed. However, XPS is only able to quasi-quantitatively determine the surface-proximity oxidation states. To account for the inadequacy of surface-sensitive XPS and AES techniques, a surface oxidation model (SOM) was proposed for the ellipsometric modeling of the mixed-valence system. Furthermore, by conducting air thermal oxidation (ATO) experiments, the four sets of fitting parameters of SOM were decreased to three, lowering the system complexity. This study is expected to help with the analysis of vanadium oxide mixed-valence systems and other multivalent metal oxide systems. Full article

(This article belongs to the Special Issue Nano-Photonics: Subwavelength Optical Elements, Metasurfaces, Plasmonics and Quantum Photonics: 2nd Edition)

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16 pages, 4215 KiB

Open AccessReview

Progress in UV Photodetectors Based on ZnO Nanomaterials: A Review of the Detection Mechanisms and Their Improvement

by Gaoda Li, Bolang Cheng, Haibo Zhang, Xinghua Zhu and Dingyu Yang

Nanomaterials 2025, 15(9), 644; https://doi.org/10.3390/nano15090644 - 24 Apr 2025

Abstract

Recent advancements in ultraviolet (UV) photodetection technology have driven intensive research on zinc oxide (ZnO) nanomaterials due to their exceptional optoelectronic properties. This review systematically examines the fundamental detection mechanisms in ZnO-based UV photodetectors (UVPDs), including photoconductivity effects, the threshold dimension phenomenon and [...] Read more.

Recent advancements in ultraviolet (UV) photodetection technology have driven intensive research on zinc oxide (ZnO) nanomaterials due to their exceptional optoelectronic properties. This review systematically examines the fundamental detection mechanisms in ZnO-based UV photodetectors (UVPDs), including photoconductivity effects, the threshold dimension phenomenon and light-modulated interface barriers. Based on these mechanisms, a large surface barrier due to surface-adsorbed O₂ is generally constructed to achieve a high sensitivity. However, this improvement is obtained with a decrease in response speed due to the slow desorption and re-adsorption processes of surface O₂ during UV light detection. Various improvement strategies have been proposed to overcome this drawback and keep the high sensitivity, including ZnO–organic semiconductor interfacing, defect engineering and doping, surface modification, heterojunction and the Schottky barrier. The general idea is to modify the adsorption state of O₂ or replace the adsorbed O₂ with another material to build a light-regulated surface or an interface barrier, as surveyed in the third section. The critical trade-off between sensitivity and response speed is also addressed. Finally, after a summary of these mechanisms and the improvement methods, this review is concluded with an outlook on the future development of ZnO nanomaterial UVPDs. Full article

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

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14 pages, 11859 KiB

Open AccessArticle

Mechanically Exfoliated Multilayer Graphene-Supported Ni-MOF Parallelogram Nanosheets for Enhanced Supercapacitor Performance

by Zhiheng Li, Junming Xu, Xinqi Ding, Haoran Zhu and Jianfeng Wu

Nanomaterials 2025, 15(9), 643; https://doi.org/10.3390/nano15090643 - 23 Apr 2025

Abstract

Metal–organic frameworks (MOFs) are regarded as advanced supercapacitor materials owing to their high surface area, redox-active sites, and porosity. However, their insufficient charge carrier mobility remains a critical limitation for practical application. Integrating MOFs with conductive carbon substrates is an effective strategy to [...] Read more.

Metal–organic frameworks (MOFs) are regarded as advanced supercapacitor materials owing to their high surface area, redox-active sites, and porosity. However, their insufficient charge carrier mobility remains a critical limitation for practical application. Integrating MOFs with conductive carbon substrates is an effective strategy to break through this limitation. However, conventional carbon materials often require complex preparation methods and pre-activation steps for use in MOF composites. Herein, multilayer graphene (MLG) mechanically exfoliated from expandable graphite is employed as a substrate, and a van der Waals force-assisted chemical deposition method is developed to directly anchor Ni-MOF onto its surface without requiring pre-activation treatment. To optimize the composite, Ni-MOFs with various mass loadings are synthesized on MLG surface. The morphological characteristics and energy storage performance of these composites are thoroughly characterized. Ni-MOF/MLG-0.30 (with a 70.8% Ni-MOF loading on MLG) features a porous stacking structure of well-crystalline Ni-MOF parallelogram nanosheets on MLG, exhibiting optimal electrochemical performance. The composite achieves 1071.4 F·g⁻¹ at 1 A·g⁻¹, and a capacitance retention of 64.9% at the elevated current density of 10 A·g⁻¹. Meanwhile, the composite maintains 63.2% of its initial capacitance after 5000 charge/discharge cycles at 4 A·g⁻¹. A hybrid supercapacitor is fabricated using Ni-MOF/MLG-0.30 cathode and activated carbon anode, delivering 27.9 Wh·kg⁻¹ energy density at 102.5 W·kg⁻¹ power output. Full article

(This article belongs to the Special Issue The Application of Nanoscale Materials in Batteries, Sensors and Supercapacitors (2nd Edition))

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16 pages, 3806 KiB

Open AccessArticle

Tunable Magnetic Heating in La_0.51Sr_0.49MnO₃ and La_0.51Dy_0.045Sr_0.445MnO₃ Nanoparticles: Frequency- and Amplitude-Dependent Behavior

by Mourad Smari, Monica Viorica Moisiuc, Mohammad Y. Al-Haik, Iordana Astefanoaei, Alexandru Stancu, Fedor Shelkovyi, Radel Gimaev, Julia Piashova, Vladimir Zverev and Yousef Haik

Nanomaterials 2025, 15(9), 642; https://doi.org/10.3390/nano15090642 - 23 Apr 2025

Abstract

The use of perovskite manganite nanoparticles in magnetic hyperthermia has attracted significant attention due to their tunable magnetic properties and high specific absorption rate (SAR). In this work, we present a combined experimental and theoretical investigation of the frequency- and amplitude-dependent magnetic heating [...] Read more.

The use of perovskite manganite nanoparticles in magnetic hyperthermia has attracted significant attention due to their tunable magnetic properties and high specific absorption rate (SAR). In this work, we present a combined experimental and theoretical investigation of the frequency- and amplitude-dependent magnetic heating behavior of La_0.51Sr_0.49MnO₃ (LSMO) and Dy-doped La_0.51Dy_0.045Sr_0.445MnO₃ (DLSMO) nanoparticles. The nanoparticles were synthesized via the sol–gel method and characterized by XRD and SEM, while SAR values were experimentally evaluated under varying magnetic field strengths (60–120 Oe) and frequencies (150–300 kHz). In parallel, theoretical modeling based on Néel and Brownian relaxation mechanisms was employed to predict SAR behavior as a function of particle size, magnetic anisotropy, and fluid viscosity. The results reveal that Dy doping enhances magnetic anisotropy, which modifies the relaxation dynamics and leads to a reduction in SAR. The model identifies the optimal nanoparticle size (~18–20 nm) and ferrofluid viscosity to maximize heating efficiency. This combined approach provides a comprehensive framework for designing and optimizing perovskite-based nanoparticles for magnetic hyperthermia applications. Full article

(This article belongs to the Section Physical Chemistry at Nanoscale)

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10 pages, 2744 KiB

Open AccessArticle

Facile Synthesis of Polypyrrole/MnO₂/Carbon Cloth Composites for Supercapacitor Electrodes

by Yan Chen, Hanyue He, Min Liu, He Xu, Haibo Zhang, Xinghua Zhu and Dingyu Yang

Nanomaterials 2025, 15(9), 641; https://doi.org/10.3390/nano15090641 - 23 Apr 2025

Abstract

In the development of flexible smart electronics, fabricating electrodes with optimized architectures to achieve superior electrochemical performance remains a significant challenge. This study presents a two-step synthesis and characterization of a polypyrrole (PPy)-MnO₂/carbon cloth (CC) nanocomposite. The MnO₂/CC substrate [...] Read more.

In the development of flexible smart electronics, fabricating electrodes with optimized architectures to achieve superior electrochemical performance remains a significant challenge. This study presents a two-step synthesis and characterization of a polypyrrole (PPy)-MnO₂/carbon cloth (CC) nanocomposite. The MnO₂/CC substrate was first prepared via the hydrothermal method, followed by uniform PPy coating through vapor-phase polymerization in the presence of an oxidizing agent. Electrochemical measurements revealed substantial enhancement in performance, with the specific capacitance increasing from 123.1 mF/cm² for the MnO₂/CC composite to 324.5 mF/cm² for the PPy/MnO₂/CC composite at a current density of 2.5 mA/cm². This remarkable improvement can be attributed to the synergistic effects between the conductive PPy polymer and MnO₂/CC substrate and the formation of additional ion transport channels facilitated by the PPy coating. This work provides valuable insights for designing high-performance electrode materials and advances the development of composite-based energy storage devices. Full article

(This article belongs to the Special Issue Application of Biomass-Derived Nanomaterials in Batteries and Supercapacitors)

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15 pages, 4751 KiB

Open AccessArticle

SnO Nanosheet Transistor with Remarkably High Hole Effective Mobility and More than Six Orders of Magnitude On-Current/Off-Current

by Kuan-Chieh Chen, Jiancheng Wu, Pheiroijam Pooja and Albert Chin

Nanomaterials 2025, 15(9), 640; https://doi.org/10.3390/nano15090640 - 23 Apr 2025

Abstract

Using novel SiO₂ surface passivation and ultraviolet (UV) light anneal, a 12 nm thick SnO p-type FET (pFET) shows hole effective mobilities (µ_eff) of more than 100 cm²/V·s and 31.1 cm²/V·s at hole densities (Q_h [...] Read more.

Using novel SiO₂ surface passivation and ultraviolet (UV) light anneal, a 12 nm thick SnO p-type FET (pFET) shows hole effective mobilities (µ_eff) of more than 100 cm²/V·s and 31.1 cm²/V·s at hole densities (Q_h) of 1 × 10¹¹ and 5 × 10¹² cm⁻², respectively. To further improve the on-current/off-current (I_ON/I_OFF), an ultra-thin 7 nm thick SnO nanosheet pFET shows a record-breaking I_ON/I_OFF of 6.9 × 10⁶ and remarkable µ_eff values of ~70 cm²/V·s and 20.7 cm²/V·s at Q_h of 1 × 10¹¹ cm⁻² and 5 × 10¹² cm⁻², respectively. This is the first report of an oxide semiconductor transistor achieving a hole effective mobility µ_eff that reaches 20% of that in single-crystal Si pFETs at an ultra-thin body thickness of 7 nm. In sharp contrast, the control SnO nanosheet pFET without surface passivation or UV anneal exhibits a small I_ON/I_OFF of 1.8 × 10⁴ and a µ_eff of only 6.1 cm²/V·s at 5 × 10¹² cm⁻² Q_h. The enhanced SnO pFET performance is attributed to reduced defects and improved quality in the SnO channel, as confirmed by decreased charges related to sub-threshold swing (SS) and threshold voltage (Vth) shift. Such a large improvement is further supported by the increased Sn²⁺ after passivation and UV anneal, as evidenced by X-ray photoelectron spectroscopy (XPS) analysis. The I_ON/I_OFF ratio exceeding six orders of magnitude, remarkably high hole µ_eff, and excellent two-month stability demonstrate that this pFET is a strong candidate for integration with SnON nFETs in next-generation ultra-high-definition displays and monolithic three-dimensional integrated circuits (3D ICs). Full article

(This article belongs to the Special Issue Integrated Circuit Research for Nanoscale Field-Effect Transistors)

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16 pages, 9146 KiB

Open AccessArticle

Aging Characteristics of ZSM-5 Zeolite on Low-Frequency Acoustic Applications

by Mingbo Guo, Yijun Wang, Lei Zhang, Junran Lu, Chang Gong, Wanning Zhang, Yuxi Fang, Xinyuan Zhu and Shunai Che

Nanomaterials 2025, 15(9), 639; https://doi.org/10.3390/nano15090639 - 23 Apr 2025

Abstract

Zeolite is increasingly recognized for its enhancement of low-frequency acoustic performance in microspeakers. The aging characteristics of zeolite have been regarded as the critical factor for the commercial viability of mobile phones products, but the mechanism remains ambiguous. Here, the low-frequency acoustic performance [...] Read more.

Zeolite is increasingly recognized for its enhancement of low-frequency acoustic performance in microspeakers. The aging characteristics of zeolite have been regarded as the critical factor for the commercial viability of mobile phones products, but the mechanism remains ambiguous. Here, the low-frequency acoustic performance of hierarchically structured ZSM-5 was investigated through aging with water and acetic acid (AA). It was discovered that water vapor augmented the resonance offset as it enhanced the structure of the zeolite, resulting in a lower water content. The resonance offset of ZSM-5 significantly decreased after the adsorption of AA vapor, as excessive AA was adsorbed through both physical and chemical adsorption, causing partial destruction of supermicropore and mesopores. The performance of ZMS-5 stored with vapor of AA and water mixture did not significantly deteriorate, indicating that water effectively protected the pores of zeolite to prevent excessive adsorption of AA. This was attributed to the fact that water was adsorbed by Brønsted acid sites of ZSM-5 more preferentially than AA, thereby avoiding excessive adsorption of AA. Full article

(This article belongs to the Section Physical Chemistry at Nanoscale)

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Nanomaterials, Volume 15, Issue 9 (May-1 2025) – 34 articles

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