Nanomaterials

18 pages, 4015 KiB

Open AccessArticle

Glancing Angle Deposited Nanostructured Tellurium Layer Against Dendrite Formation and Side Reactions in Aqueous Zn-Ion Battery Anode

by Salim Hussain, S. M. Sayem, Assem Basurrah, Tahany Rashed, Fumiya Watanabe, Noureen Siraj and Tansel Karabacak

Nanomaterials 2025, 15(12), 952; https://doi.org/10.3390/nano15120952 - 19 Jun 2025

Viewed by 192

Abstract

Aqueous zinc ion batteries (AZIBs) have considerable potential for energy storage owing to their cost-effectiveness, safety, and environmental sustainability. However, dendrite formation, hydrogen evolution reaction (HER), and corrosion of the bare zinc (B-Zn) anode tremendously impact the performance degradation and premature failure of [...] Read more.

Aqueous zinc ion batteries (AZIBs) have considerable potential for energy storage owing to their cost-effectiveness, safety, and environmental sustainability. However, dendrite formation, hydrogen evolution reaction (HER), and corrosion of the bare zinc (B-Zn) anode tremendously impact the performance degradation and premature failure of AZIBs. This study introduces a glancing angle deposition (GLAD) approach during the sputtering process to fabricate tellurium nanostructured (TeNS) at the zinc (Zn) anode to avoid the aforementioned issues with the B-Zn anode. Three different deposition times (5, 10, and 30 min) were used to prepare TeNS at the Zn anode. The morphology, crystallinity, composition, and wettability of the TeNSs were analyzed. The TeNSs served as hydrophilic sites and a protective layer, facilitating uniform Zn nucleation and plating while inhibiting dendrite formation and side reactions. Consequently, the symmetric cell with TeNS deposited on the Zn anode for 10 min (Te@Zn_10 min) demonstrated an enhanced cycling stability of 350 h, the lowest nucleation overpotential of 10.65 mV at a current density of 1 mA/cm², and an areal capacity of 0.5 mAh/cm². The observed enhancement in the cycling stability and reduction in the nucleation overpotential can be attributed to the optimal open area fraction of the TeNSs on the Zn surface, which promotes uniform Zn deposition while effectively suppressing side reactions. Full article

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

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20 pages, 2485 KiB

Open AccessArticle

Optimizing Sunscreen Safety: The Impact of TiO₂ Particle Size on Toxicity and Biocompatibility

by Adriana S. Maddaleno, Clàudia Casellas, Elisabet Teixidó, Laia Guardia-Escote, Maria Pilar Vinardell and Montserrat Mitjans

Nanomaterials 2025, 15(12), 951; https://doi.org/10.3390/nano15120951 - 19 Jun 2025

Viewed by 246

Abstract

The use of UV filters is a well-established strategy for preventing skin cancer and photoaging. Among inorganic filters, titanium dioxide (TiO₂) provides excellent protection against both UVA and UVB radiation. Moreover, the use of such inorganic filters at the nano-sized scale [...] Read more.

The use of UV filters is a well-established strategy for preventing skin cancer and photoaging. Among inorganic filters, titanium dioxide (TiO₂) provides excellent protection against both UVA and UVB radiation. Moreover, the use of such inorganic filters at the nano-sized scale has increased their acceptability because it ensures the cosmetically desired transparency in sunscreens that consumers demand. However, concerns remain regarding the potential toxicity of TiO₂ nanoparticles, and discussion about their use in pharmaceuticals and cosmetics is still in progress. Their increased (bio)reactivity compared to bulk materials may lead to DNA damage. Furthermore, their capacity to cross dermal, respiratory, and gastrointestinal membranes remains a subject of debate. This study is therefore designed to assess and contrast the toxicological characteristics of a pair of commercially available titanium (IV) oxide sunscreens differing in particle size—microscale versus nanoscale. First, the morphology and hydrodynamic diameter of the TiO₂ nanoparticles were characterized. Then, potential interactions and/or interferences of these nanoparticles with the methods used to evaluate cytotoxic behavior were studied. Finally, the hemocompatibility, cytotoxicity, phototoxicity, and genotoxicity of both micro- and nano-sized TiO₂ were evaluated using human keratinocytes. Full article

(This article belongs to the Section Biology and Medicines)

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26 pages, 1710 KiB

Open AccessReview

Impacts of Cerium Dioxide Nanoparticles on the Soil–Plant System and Their Potential Agricultural Applications

by Nadeesha L. Ukwattage and Zhang Zhiyong

Nanomaterials 2025, 15(12), 950; https://doi.org/10.3390/nano15120950 - 19 Jun 2025

Viewed by 134

Abstract

Cerium dioxide nanoparticles (CeO₂-NPs) are increasingly used in various industrial applications, leading to their inevitable release into the environment including the soil ecosystem. In soil, CeO₂-NPs are taken up by plants, translocated, and accumulated in plant tissues. Within plant [...] Read more.

Cerium dioxide nanoparticles (CeO₂-NPs) are increasingly used in various industrial applications, leading to their inevitable release into the environment including the soil ecosystem. In soil, CeO₂-NPs are taken up by plants, translocated, and accumulated in plant tissues. Within plant tissues, CeO₂-NPs have been shown to interfere with critical metabolic pathways, which may affect plant health and productivity. Moreover, their presence in soil can influence soil physico-chemical and biological properties, including microbial communities within the rhizosphere, where they can alter microbial physiology, diversity, and enzymatic activities. These interactions raise concerns about the potential disruption of plant–microbe symbiosis essential for plant nutrition and soil health. Despite these challenges, CeO₂-NPs hold potential as tools for enhancing crop productivity and resilience to stress, such as drought or heavy metal contamination. However, understanding the balance between their beneficial and harmful effects is crucial for their safe application in agriculture. To date, the overall impact of CeO₂-NPs on soil -plant system and the underlying mechanism remains unclear. Therefore, this review analyses the recent research findings to provide a comprehensive understanding of the fate of CeO₂-NPs in soil–plant systems and the implications for soil health, plant growth, and agricultural productivity. As the current research is limited by inconsistent findings, often due to variations in experimental conditions, it is essential to study CeO₂-NPs under more ecologically relevant settings. This review further emphasizes the need for future research to assess the long-term environmental impacts of CeO₂-NPs in soil–plant systems and to develop guidelines for their responsible use in sustainable agriculture. Full article

(This article belongs to the Special Issue Interplay between Nanomaterials and Plants)

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14 pages, 2652 KiB

Open AccessArticle

Rational Construction of Nano-Scaled FeOOH/NiFe-LDH for Efficient Water Splitting

by Juan Yu, Xiubing Fu, Haoqi Wang, Shun Lu and Bing Li

Nanomaterials 2025, 15(12), 949; https://doi.org/10.3390/nano15120949 - 18 Jun 2025

Viewed by 202

Abstract

In this paper, we use the facile approach for preparing novel, low-cost, efficient electrocatalysts for electrocatalytic water splitting. Interfacial engineering can significantly enhance the intrinsic performance of electrocatalysts. Herein, self-supporting FeOOH/NiFe-layered double hydroxide (LDH) nanosheet arrays were synthesized via hydrothermal and impregnation methods. [...] Read more.

In this paper, we use the facile approach for preparing novel, low-cost, efficient electrocatalysts for electrocatalytic water splitting. Interfacial engineering can significantly enhance the intrinsic performance of electrocatalysts. Herein, self-supporting FeOOH/NiFe-layered double hydroxide (LDH) nanosheet arrays were synthesized via hydrothermal and impregnation methods. The resulting FeOOH/NiFe-LDH can provide more active regions, which provide more active regions for co-reaction to proceed and accelerates electron transmit processes. Additionally, the amorphous FeOOH provides abundant active sites with low coordination, leading to excellent activity. The FeOOH/NiFe-LDH demonstrates remarkable two half-reaction electrocatalytic activity, along with excellent overpotentials of 168 mV (OER) and 155 mV (HER). This research introduces a sophisticated and scalable methodology for the creation of remarkably efficient and resilient alkaline conditions specifically designed for the HER and OER. Full article

(This article belongs to the Special Issue Hybrid Nanomaterials and/or Nanocomposites for Photo(Electro-) Catalytic Applications)

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33 pages, 4701 KiB

Open AccessReview

Machine-Learning-Guided Design of Nanostructured Metal Oxide Photoanodes for Photoelectrochemical Water Splitting: From Material Discovery to Performance Optimization

by Xiongwei Liang, Shaopeng Yu, Bo Meng, Yongfu Ju, Shuai Wang and Yingning Wang

Nanomaterials 2025, 15(12), 948; https://doi.org/10.3390/nano15120948 - 18 Jun 2025

Viewed by 202

Abstract

The rational design of photoanode materials is pivotal for advancing photoelectrochemical (PEC) water splitting toward sustainable hydrogen production. This review highlights recent progress in the machine learning (ML)-assisted development of nanostructured metal oxide photoanodes, focusing on bridging materials discovery and device-level performance optimization. [...] Read more.

The rational design of photoanode materials is pivotal for advancing photoelectrochemical (PEC) water splitting toward sustainable hydrogen production. This review highlights recent progress in the machine learning (ML)-assisted development of nanostructured metal oxide photoanodes, focusing on bridging materials discovery and device-level performance optimization. We first delineate the fundamental physicochemical criteria for efficient photoanodes, including suitable band alignment, visible-light absorption, charge carrier mobility, and electrochemical stability. Conventional strategies such as nanostructuring, elemental doping, and surface/interface engineering are critically evaluated. We then discuss the integration of ML techniques—ranging from high-throughput density functional theory (DFT)-based screening to experimental data-driven modeling—for accelerating the identification of promising oxides (e.g., BiVO₄, Fe₂O₃, WO₃) and optimizing key parameters such as dopant selection, morphology, and catalyst interfaces. Particular attention is given to surrogate modeling, Bayesian optimization, convolutional neural networks, and explainable AI approaches that enable closed-loop synthesis-experiment-ML frameworks. ML-assisted performance prediction and tandem device design are also addressed. Finally, current challenges in data standardization, model generalizability, and experimental validation are outlined, and future perspectives are proposed for integrating ML with automated platforms and physics-informed modeling to facilitate scalable PEC material development for clean energy applications. Full article

(This article belongs to the Special Issue Nanomaterials for Novel Photoelectrochemical Devices)

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11 pages, 2381 KiB

Open AccessArticle

High-Performance and Fabrication-Tolerant 3 dB Adiabatic Coupler Based on Ultralow-Loss Silicon Waveguide by Tri-Layer Hard Mask Etching Process

by Ke Zhang, Yunchu Yu, Nanfei Zhu, Senlin Zhang, Jie Sun, Shijin Ding and David Wei Zhang

Nanomaterials 2025, 15(12), 947; https://doi.org/10.3390/nano15120947 - 18 Jun 2025

Viewed by 171

Abstract

Silicon photonics has emerged as critical for advancing photonic integrated circuits (PICs), but waveguide losses, primarily resulting from sidewall roughness, remain a primary challenge. In this work, we demonstrate a tri-layer hard mask etching process that produces strip silicon waveguides with propagation losses [...] Read more.

Silicon photonics has emerged as critical for advancing photonic integrated circuits (PICs), but waveguide losses, primarily resulting from sidewall roughness, remain a primary challenge. In this work, we demonstrate a tri-layer hard mask etching process that produces strip silicon waveguides with propagation losses as low as 1.48 dB/cm, i.e., a 37% improvement over the conventional Si₃N₄ hard mask technique. Based on the abovementioned approach, the fabricated 3 dB adiabatic directional couplers achieve a nearly ideal splitting ratio of 50.2:49.8 as well as an excess loss of 0.067 dB. These results indicate that the tri-layer hard mask etching process enables scalable and ultralow-loss PICs to be fabricated for high-speed optical interconnects and quantum computing systems. Full article

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

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10 pages, 4005 KiB

Open AccessArticle

Novel 4H-SiC Double-Trench MOSFETs with Integrated Schottky Barrier and MOS-Channel Diodes for Enhanced Breakdown Voltage and Switching Characteristics

by Peiran Wang, Chenglong Li, Chenkai Deng, Qinhan Yang, Shoucheng Xu, Xinyi Tang, Ziyang Wang, Wenchuan Tao, Nick Tao, Qing Wang and Hongyu Yu

Nanomaterials 2025, 15(12), 946; https://doi.org/10.3390/nano15120946 - 18 Jun 2025

Viewed by 190

Abstract

In this study, a novel silicon carbide (SiC) double-trench MOSFET (DT-MOS) combined Schottky barrier diode (SBD) and MOS-channel diode (MCD) is proposed and investigated using TCAD simulations. The integrated MCD helps inactivate the parasitic body diode when the device is utilized as a [...] Read more.

In this study, a novel silicon carbide (SiC) double-trench MOSFET (DT-MOS) combined Schottky barrier diode (SBD) and MOS-channel diode (MCD) is proposed and investigated using TCAD simulations. The integrated MCD helps inactivate the parasitic body diode when the device is utilized as a freewheeling diode, eliminating bipolar degradation. The adjustment of SBD position provides an alternative path for reverse conduction and mitigates the electric field distribution near the bottom source trench region. As a result of the Schottky contact adjustment, the reverse conduction characteristics are less influenced by the source oxide thickness, and the breakdown voltage (BV) is largely improved from 800 V to 1069 V. The gate-to-drain capacitance is much lower due to the removal of the bottom oxide, bringing an improvement to the turn-on switching rise time from 2.58 ns to 0.68 ns. These optimized performances indicate the proposed structure with both SBD and MCD has advantages in switching and breakdown characteristics. Full article

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

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16 pages, 4395 KiB

Open AccessArticle

Nanoporous Copper Films via Dynamic Hydrogen Bubbling: A Promising SERS Substrate for Sensitive Detection of Methylene Blue

by Noor Tayyaba, Stefano Zago, Andrea Giura, Gianluca Fiore, Luigi Ribotta, Federico Scaglione and Paola Rizzi

Nanomaterials 2025, 15(12), 945; https://doi.org/10.3390/nano15120945 - 18 Jun 2025

Viewed by 175

Abstract

Cu-based nanomaterials have received considerable attention as promising and cost-effective substrates for surface-enhanced Raman spectroscopy (SERS) applications despite their relatively low enhancement factor (EF) compared to noble metals like gold and silver. In this study, a fast and affordable synthesis route is proposed [...] Read more.

Cu-based nanomaterials have received considerable attention as promising and cost-effective substrates for surface-enhanced Raman spectroscopy (SERS) applications despite their relatively low enhancement factor (EF) compared to noble metals like gold and silver. In this study, a fast and affordable synthesis route is proposed to obtain a three-dimensional porous copper film (NPC) via an electrodeposition technique based on the dynamic hydrogen bubbling template (DHBT). Two sets of NPC film were synthesized, one without additives and the other with cetyltrimethylammonium bromide (CTAB). The impacts of deposition time on the NPCs’ porous morphology, thickness, and SERS performance were systematically investigated. With the optimal deposition time, the nanopore sizes could be tailored from 26.8 to 73 μm without additives and from 12.8 to 24 µm in the presence of CTAB. The optimal additive-free NPC film demonstrated excellent SERS performance at 180 s of deposition, while the CTAB-modified film showed strong enhancement at 120 s towards methylene blue (MB), a highly toxic dye, achieving a detection limit of 10⁻⁶ M. Additionally, the samples with CTAB showed better efficiency than those without CTAB. The calculated EF of NPC was found to be 5.9 × 10³ without CTAB and 2.5 × 10³ with the CTAB, indicating the potential of NPC as a cost-effective candidate for high-performance SERS substrates. This comprehensive study provides insights into optimizing the structural morphology of the NPCs to maximize their SERS enhancement factor and improve their detection sensitivity toward MB, thus overcoming the limitations associated with conventional copper-based SERS substrates. Full article

(This article belongs to the Section Nanofabrication and Nanomanufacturing)

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8 pages, 2235 KiB

Open AccessArticle

In Situ Synthesis of Copper Nanoparticles on Biocarbon Sheets for Surface-Enhanced Raman Scattering

by Jianqiang Wei, Zelong Zhou, Junchao Qian, Yaping Wang, Jun Chen and Yunfei Sun

Nanomaterials 2025, 15(12), 944; https://doi.org/10.3390/nano15120944 - 18 Jun 2025

Viewed by 154

Abstract

A copper nanoparticles@porous biocarbon substrate was designed for Surface-Enhanced Raman Spectroscopy (SERS) via a simple reduction method. In the detection of three trace antibiotics, the substrate exhibits a very high Raman enhancement efficiency. This is partly because the biocarbon is rich in meso-micropores, [...] Read more.

A copper nanoparticles@porous biocarbon substrate was designed for Surface-Enhanced Raman Spectroscopy (SERS) via a simple reduction method. In the detection of three trace antibiotics, the substrate exhibits a very high Raman enhancement efficiency. This is partly because the biocarbon is rich in meso-micropores, which can rapidly trap target molecules. On the other hand, the copper nanoparticles embedded on the surface of the carbon sheets generate a large number of plasmonic hotspots, leading to an increase in Raman signal intensity. These results suggest that this substrate has utility for SERS applications in food safety, medicine, and water pollution detection. Full article

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

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33 pages, 4158 KiB

Open AccessReview

Graphene-Based Plasmonic Antenna for Advancing Nano-Scale Sensors

by Waqas Ahmad, Yihuan Wang, Guangqing Du, Qing Yang and Feng Chen

Nanomaterials 2025, 15(12), 943; https://doi.org/10.3390/nano15120943 - 18 Jun 2025

Viewed by 272

Abstract

The integration of two-dimensional graphene with gold nanostructures has significantly advanced surface plasmon resonance (SPR)-based optical biosensors, due to graphene’s exceptional optical, electronic, and surface properties. This review examines recent developments in graphene-based hybrid nanomaterials designed to enhance SPR sensor performance. The synergistic [...] Read more.

The integration of two-dimensional graphene with gold nanostructures has significantly advanced surface plasmon resonance (SPR)-based optical biosensors, due to graphene’s exceptional optical, electronic, and surface properties. This review examines recent developments in graphene-based hybrid nanomaterials designed to enhance SPR sensor performance. The synergistic combination of graphene and other functional materials enables superior plasmonic sensitivity, improves biomolecular interaction, and enhances signal transduction. Key focus areas include the fundamental principle of graphene-enhanced SPR, the functional advantages of graphene hybrid platforms, and their recent applications in detecting biomolecules, disease biomarkers, and pathogens. Finally, current limitations and potential future perspectives are discussed, highlighting the transformative potential of these hybrid nanomaterials in next-generation optical biosensing Full article

(This article belongs to the Special Issue Applications of Nanomaterials in Optical Sensors, Second Edition)

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13 pages, 1947 KiB

Open AccessArticle

Photothermal Performance of 2D Material-Based Nanoparticles for Biomedical Applications

by Amir Eghbali, Nikolay V. Pak, Aleksey V. Arsenin, Valentyn Volkov and Andrey A. Vyshnevyy

Nanomaterials 2025, 15(12), 942; https://doi.org/10.3390/nano15120942 - 18 Jun 2025

Viewed by 223

Abstract

Photothermal therapy (PTT) is one of the rapidly developing methods for cancer treatment based on the strong light-to-heat conversion by nanoparticles. Over the past decade, the palette of photonic materials has expanded drastically, and nanoparticle fabrication techniques can now preserve the optical response [...] Read more.

Photothermal therapy (PTT) is one of the rapidly developing methods for cancer treatment based on the strong light-to-heat conversion by nanoparticles. Over the past decade, the palette of photonic materials has expanded drastically, and nanoparticle fabrication techniques can now preserve the optical response of a bulk material in produced nanoparticles. This progress potentially holds opportunities for the efficiency enhancement of PTT, which have not fully explored yet. Here we study the photothermal performance of spherical nanoparticles (SNs) composed of novel two-dimensional (2D) and conventional materials with existing or potential applications in photothermal therapy such as MoS₂, PdSe₂, Ti₃C₂, TaS₂, and TiN. Using the Mie theory, we theoretically analyze the optical response of SNs across various radii of 5–100 nm in the near-infrared (NIR) region with a particular focus on the therapeutic NIR-II range (1000–1700 nm) and radii below 50 nm. Our calculations reveal distinct photothermal behaviors: Large (radius > 50 nm) nanoparticles made of van der Waals semiconductors and PdSe₂ perform exceptionally well in the NIR-I range (750–950 nm) due to excitonic optical responses, while Ti₃C₂ nanoparticles achieve broad effectiveness across both NIR zones due to their dual dielectric/plasmonic properties. Small TiN SNs excel in the NIR-I zone due to the plasmonic response of TiN at shorter wavelengths. Notably, the van der Waals metal TaS₂ emerges as the most promising photothermal transduction agent in the NIR-II region, particularly for smaller nanoparticles, due to its plasmonic resonance. Our insights lay a foundation for designing efficient photothermal transduction agents, with significant implications for cancer therapy and other biomedical applications. Full article

(This article belongs to the Special Issue Nanostructured Materials and Coatings for Biomedical Applications)

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13 pages, 3083 KiB

Open AccessArticle

Density-Based Characterization of Microplastics via Cross-Halbach Magnetic Levitation

by Chenxin Lyu, Chengqian Zhang, Baocai Zhang, Xuebin Ni, Hongchao Wang and Peng Zhao

Nanomaterials 2025, 15(12), 941; https://doi.org/10.3390/nano15120941 - 17 Jun 2025

Viewed by 119

Abstract

The analysis of microplastics poses significant challenges for conventional characterization techniques due to their small size and low concentrations. Magnetic levitation (MagLev), already proven effective for microscale material testing, provides a robust solution for sensitive, accessible, and untethered characterization of such materials. In [...] Read more.

The analysis of microplastics poses significant challenges for conventional characterization techniques due to their small size and low concentrations. Magnetic levitation (MagLev), already proven effective for microscale material testing, provides a robust solution for sensitive, accessible, and untethered characterization of such materials. In this paper, we propose a Cross-Halbach magnetic levitation device to measure the densities of microscale plastic materials. Common types of plastic samples, varying in size and concentration, are successfully levitated, and the levitation times are recorded. The samples of common microplastic materials are characterized in less than 180 s. The characterized density values are validated against theoretical results, enabling density-based identification of microplastics. The experimental results demonstrate that the magnetic levitation method is suitable for the characterization of small-sized plastic materials, and the high-speed, low-volume measurement of plastic samples lays the foundation for future applications such as detection, separation, and recycling of ultrafine materials. Full article

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12 pages, 2376 KiB

Open AccessArticle

Stable Vacancy-Rich Sodium Vanadate as a Cathode for High-Performance Aqueous Zinc-Ion Batteries

by Zhibo Xie, Yongru Qu, Fuwei Kong, Ruizheng Zhao and Xianfen Wang

Nanomaterials 2025, 15(12), 940; https://doi.org/10.3390/nano15120940 - 17 Jun 2025

Viewed by 200

Abstract

Vanadium-based cathodes are promising for aqueous zinc-ion batteries (ZIBs) due to the large interlayer distance. However, the poor stability of electrode materials due to the dissolution effects has severely hindered the commercial development. To address this challenge, we propose an in situ NH [...] Read more.

Vanadium-based cathodes are promising for aqueous zinc-ion batteries (ZIBs) due to the large interlayer distance. However, the poor stability of electrode materials due to the dissolution effects has severely hindered the commercial development. To address this challenge, we propose an in situ NH₄⁺ pre-intercalation strategy to enhance the electrochemical performance of Na_0.76V₆O₁₅ (NaVO), thereby optimizing its structural stability and ionic conductivity. Moreover, NH₄⁺ pre-intercalation introduced a large number of oxygen vacancies and defects into the material, causing the reduction of V⁵⁺ to V⁴⁺. This transformation suppresses the dissolution and enhances its conductivity, thereby significantly improving the electrochemical performance. This modified NaNVO cathodes deliver a higher capacity of 456 mAh g⁻¹ at 0.1 A g⁻¹, with a capacity retention of 88% after 140 cycles and a long lifespan, maintaining 99% of its initial capacity after 2300 cycles. This work provided a new way to optimize the cathode for aqueous zinc-ion batteries. Full article

(This article belongs to the Special Issue Nanostructured Materials for Energy Storage)

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14 pages, 3628 KiB

Open AccessArticle

Phase Evolution of High-Entropy Stannate Pyrochlore Oxide Synthesized via Glycine-Assisted Sol–Gel Synthesis as a Thermal Barrier Coating Material

by Mariappan Anandkumar, Kannan Pidugu Kesavan, Shanmugavel Sudarsan, Dmitry Evgenievich Zhivulin, Natalia Aleksandrovna Shaburova, Ahmad Ostovari Moghaddam, Ksenia Sergeevna Litvinyuk and Evgeny Alekseevich Trofimov

Nanomaterials 2025, 15(12), 939; https://doi.org/10.3390/nano15120939 - 17 Jun 2025

Viewed by 155

Abstract

High-entropy ceramics have gained wider attention due to their structural integrity and stability, which can be used in various functional applications. Especially, high-entropy oxides exhibit excellent thermal stability, particularly at high temperatures. Thermal barrier coating materials must demonstrate good thermal stability without any [...] Read more.

High-entropy ceramics have gained wider attention due to their structural integrity and stability, which can be used in various functional applications. Especially, high-entropy oxides exhibit excellent thermal stability, particularly at high temperatures. Thermal barrier coating materials must demonstrate good thermal stability without any phase transformation or phase separation, which is critical in aerospace and energy conversion applications. To address this, we have prepared new high-entropy stannate pyrochlore oxide nanoparticles with the composition (Gd_0.2Nd_0.2La_0.2Pr_0.2Sm_0.2)₂Sn₂O₇ through a simple glycine-assisted sol–gel synthesis. The phase evolution was probed at different heat-treatment temperatures from 1000 °C to 1500 °C. Among the temperatures investigated, a single-phase pyrochlore oxide was formed from 1300 °C without any impurity or phase separation. The obtained nanoparticles were characterized using various techniques, including X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM), nanoindentation, and dilatometry to investigate their physiochemical and mechanical properties. The Vickers hardness of high-entropy oxides is 4.2 ± 0.33 GPa, while a thermal expansion coefficient (TEC) of 8.7 × 10⁻⁶ K⁻¹ at 900 °C is calculated. The results show that the prepared high-entropy pyrochlore oxide can be a suitable candidate for thermal barrier coating. Full article

(This article belongs to the Special Issue Preparation and Characterization of Nanomaterials)

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28 pages, 3751 KiB

Open AccessArticle

Quantum Mechanics MP2 and CASSCF Study of Coordinate Quasi-Double Bonds in Cobalt(II) Complexes as Single Molecule Magnets

by Yuemin Liu, Salah S. Massoud, Oleg N. Starovoytov, Tariq Altalhi, Yunxiang Gao and Boris I. Yakobson

Nanomaterials 2025, 15(12), 938; https://doi.org/10.3390/nano15120938 - 17 Jun 2025

Viewed by 512

Abstract

Co(II) complexes have shown promising applications as single-molecule magnets (SMMs) in quantum computing and structural biology. Deciphering the Co(II) complexes may facilitate the development of SMM materials. Structural optimizations and calculations of chemical and magnetic properties were performed for Co(II) complexes with a [...] Read more.

Co(II) complexes have shown promising applications as single-molecule magnets (SMMs) in quantum computing and structural biology. Deciphering the Co(II) complexes may facilitate the development of SMM materials. Structural optimizations and calculations of chemical and magnetic properties were performed for Co(II) complexes with a tripodal tetradentate phenolate-amine ligand using MP2/aug-cc-pvdz, MP2/Def2svp, and CASSCF/Def2svp methods. The Second Order Perturbation Theory Analysis of Fock Matrix in NBO Basis unravels that Co(II) ions form unusual coordinate quasi-double bonds with ligand oxygen donor atoms, and the bond strengths range from 142.01 kcal/mol to 167.36 kcal/mol but lack further spectrometric evidence. The average 151.70 kcal/mol of the Co(II-O coordinates quasi-double bonds are formed mainly by two lone pairs of electrons from the ligand phenolate donor oxygen atoms. Dispersion forces contribute 24%, 28%, 27%, and 31% to the Co(II)-ligand interaction. Theoretical results of ZFS D, transversal ZFS E, and g-factor agree well with the experimental values. Magnetic susceptibility parameters calculated based on 5 doublet roots account for 85% of results computed 40 doublet roots are specified. These insights may aid in the rational design of SMM materials and Co(II) porphyrin fullerene conjugate for CO₂ electroreduction with superior magnetic properties. Full article

(This article belongs to the Special Issue Fundamental and Applied Aspects of the Physics in Low-Dimensional Systems)

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22 pages, 7182 KiB

Open AccessArticle

Nanovesicles and Human Skin Interaction: A Comparative Ex-Vivo Study

by Elisabetta Esposito, Valentyn Dzyhovski, Federico Santamaria, Catia Contado, Cinzia Brenna, Luca Maria Neri, Paola Secchiero, Francesco Spinozzi, Alessia Pepe, Michał Rawski, Maria Grazia Ortore, Paolo Mariani, Andrea Galvan, Laura Calderan and Manuela Malatesta

Nanomaterials 2025, 15(12), 937; https://doi.org/10.3390/nano15120937 - 16 Jun 2025

Viewed by 145

Abstract

The topical administration of drugs on the skin by nanovesicular systems can represent a tool to treat skin pathologies. The study of nanovesicle biodistribution after skin administration is crucial to understanding their transdermal potential. A formative study enabled us to investigate the influence [...] Read more.

The topical administration of drugs on the skin by nanovesicular systems can represent a tool to treat skin pathologies. The study of nanovesicle biodistribution after skin administration is crucial to understanding their transdermal potential. A formative study enabled us to investigate the influence of some methods in the production of nanovesicles based on phosphatidylcholine, differing in their ethanol amount. Particularly, both liposomes and ethosomes produced by different methods, i.e., microfluidics and solvent injection, were considered. The evaluation of size distribution, shape and internal morphology was performed using photon correlation spectroscopy, cryogenic electron microscopy, hyperspectral dark-field microscopy and small-angle X-ray scattering. Transmission electron microscopy was then used to observe and compare the transdermal passage of selected liposomes and ethosomes applied to human skin explants in a bioreactor. The mean diameters of nanovesicles prepared by the ethanol injection method were smaller with respect to those obtained by microfluidics, measuring roughly 140 and 230 nm, respectively. The uni- or multilamellar ultrastructure of the vesicles was influenced by the solvent injection procedure. Ultrastructural analysis of skin penetration revealed (i) the ability of intact vesicles to cross the different skin layers, with ethosomes produced by the water injection method showing greater transdermal potential and (ii) the role of ethanol as a penetration enhancer. Full article

(This article belongs to the Special Issue Green Nanoparticles for Topical Administration of Drugs)

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19 pages, 4498 KiB

Open AccessArticle

Preparation and Properties of Magnetically Responsive Graphene/Boron Nitride/Iron Oxide Filler Composite Epoxy Resin Materials

by Yiheng Yu, Duo Zhang, Hui He, Chaogui Luo and Ming Zhou

Nanomaterials 2025, 15(12), 936; https://doi.org/10.3390/nano15120936 - 16 Jun 2025

Viewed by 147

Abstract

In this paper, magnetically responsive graphene/boron nitride/iron oxide fillers were prepared by growing iron oxide on the surface of graphene/boron nitride fillers via liquid-phase reaction. By adding the composite filler into the epoxy resin and utilising magnetic field-assisted curing, the composites were prepared [...] Read more.

In this paper, magnetically responsive graphene/boron nitride/iron oxide fillers were prepared by growing iron oxide on the surface of graphene/boron nitride fillers via liquid-phase reaction. By adding the composite filler into the epoxy resin and utilising magnetic field-assisted curing, the composites were prepared to effectively improve the thermal conductivity of the composites while maintaining the insulating properties. The thermal conductivity of the composite filler is 2.1 Wm⁻¹K⁻¹, and the volume resistance is 4.63 × 10¹² Ω·cm when the mass ratio of the composite filler is 25%, and the thermal stability and ablation resistance of the composites are improved compared with that of the pure epoxy resin. Full article

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

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13 pages, 2154 KiB

Open AccessArticle

Electrochemical Performance and Time Stability of the Solid Oxide Cells with a (La,Sr)(Ga,Fe,Mg)O_3−δ Electrolyte and (La,Sr)(Fe,Ga,Mg)O_3−δ Electrodes

by Egor Gordeev, Ekaterina Antonova and Denis Osinkin

Nanomaterials 2025, 15(12), 935; https://doi.org/10.3390/nano15120935 - 16 Jun 2025

Viewed by 210

Abstract

Electrochemical devices on solid electrolytes are closely considered from the point of view of efficient utilization of environmental resources in order to obtain a variety of products, including those with high added cost. This study provides insight into the functionality of electrochemical cells [...] Read more.

Electrochemical devices on solid electrolytes are closely considered from the point of view of efficient utilization of environmental resources in order to obtain a variety of products, including those with high added cost. This study provides insight into the functionality of electrochemical cells that have been designed with a specific configuration. These cells have the same ionic composition of the anode, cathode, and electrolyte. This was achieved by iron doping of highly conductive (La,Sr)(Ga,Mg)O_3−δ electrolyte, and gallium and magnesium doping of the electrode material based on (La,Sr)FeO_3−δ. The main focus in this study is on the electrochemical behavior of such cells depending on the oxygen partial pressure in the gas phase, as well as the stability of the electrochemical performance over time for more than 950 h of testing. According to the obtained results, the electrochemical cell with a completely identical ionic composition of electrodes La_0.6Sr_0.4Fe_0.85Ga_0.1Mg_0.05O_3−δ and electrolyte (La_0.8Sr_0.2)_0.98Ga_0.7Fe_0.1Mg_0.2O_3−δ demonstrated the best set of optimal performances. This consists of excellent chemical compatibility, high electrochemical activity (0.08 Ω cm² in air at 800 °C), and a minor degradation rate. Full article

(This article belongs to the Special Issue Synthesis and Applications of Nanoscale Materials for Renewable Energy)

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9 pages, 1926 KiB

Open AccessCommunication

Surface Modification of Fe-Based Perovskite Oxide via Sr_0.95Ce_0.05CoO_3−δ Infiltration: A Strategy for Thermochemical Stability

by Taeheun Lim and Heesoo Lee

Nanomaterials 2025, 15(12), 934; https://doi.org/10.3390/nano15120934 - 16 Jun 2025

Viewed by 273

Abstract

Cobalt-based perovskite oxides exhibit remarkable catalytic activity owing to abundant oxygen vacancies and mixed ionic–electronic conductivity, but they suffer from structural instability. In contrast, iron-based perovskite oxides are thermochemically stable under oxidizing and reducing conditions but are catalytically limited. To combine these complementary [...] Read more.

Cobalt-based perovskite oxides exhibit remarkable catalytic activity owing to abundant oxygen vacancies and mixed ionic–electronic conductivity, but they suffer from structural instability. In contrast, iron-based perovskite oxides are thermochemically stable under oxidizing and reducing conditions but are catalytically limited. To combine these complementary properties, a composite perovskite oxide was designed and prepared by infiltrating Sr_0.95Ce_0.05CoO_3−δ (SCC) into Ba_0.5Sr_0.5Fe_0.8Cu_0.2O_3−δ (BSFC). The SCC precursor solution was dropwise applied to a BSFC|SDC|BSFC symmetric cell and heat treated. Surface morphology and compositional analyses confirmed the distribution of SCC nanoparticles on the BSFC surface. High-temperature X-ray diffraction and Rietveld refinement results revealed that both BSFC and SCC retained the cubic perovskite structure (space group Pm-3m) at room temperature. No phase transition or secondary phase formation was observed during heating from 200 to 800 °C, and the peak shifts are attributed to thermal expansion and possible oxygen loss at elevated temperatures. Upon cooling, the diffraction patterns returned to their initial state, confirming a high-temperature structural stability. XPS analysis showed an increase in the satellite peak intensity associated with Fe³⁺ after SCC infiltration, and the average oxidation state of Fe decreased from 3.52 (BSFC) to 3.49 (composite perovskite oxide). The O 1s spectra revealed a higher relative content of surface-adsorbed oxygen species in the composite, indicating increased oxygen vacancy formation. Full article

(This article belongs to the Section Nanocomposite Materials)

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32 pages, 2412 KiB

Open AccessReview

Bio-Based Nanomaterials for Groundwater Arsenic Remediation: Mechanisms, Challenges, and Future Perspectives

by Md. Mahbubur Rahman, Md. Nizam Uddin, Md Mahadi Hassan Parvez, Md. Abdullah Al Mohotadi and Jannatul Ferdush

Nanomaterials 2025, 15(12), 933; https://doi.org/10.3390/nano15120933 - 16 Jun 2025

Viewed by 332

Abstract

Arsenic contamination in water poses a significant global health risk, necessitating efficient and sustainable remediation strategies. Arsenic contamination affects groundwater in at least 106 countries, potentially exposing over 200 million people to elevated levels, primarily through contaminated drinking water. Among the most affected [...] Read more.

Arsenic contamination in water poses a significant global health risk, necessitating efficient and sustainable remediation strategies. Arsenic contamination affects groundwater in at least 106 countries, potentially exposing over 200 million people to elevated levels, primarily through contaminated drinking water. Among the most affected regions, Bangladesh remains a critical case study, where widespread reliance on shallow tubewells has resulted in one of the largest mass poisonings in history. Bio-based nanomaterials have emerged as promising solutions due to their eco-friendly nature, cost-effectiveness, and high adsorption capabilities. These nanomaterials offer a sustainable approach to arsenic remediation, utilizing materials like biochar, modified biopolymers, and bio-based aerogels, which can effectively adsorb arsenic and other pollutants. The use of environmentally friendly nanostructures provides a potential option for improving the efficiency and sustainability of arsenic remediation from groundwater. This review explores the mechanisms underlying arsenic remediation using such nanomaterials, including adsorption, filtration/membrane technology, photocatalysis, redox reactions, complexation, ion exchange, and coagulation–flocculation. Despite their potential, challenges such as scalability, stability, and regeneration hinder widespread application. We discuss recent advancements in material design, surface modifications, and hybrid systems that enhance performance. Finally, future perspectives are highlighted, including the integration of these bio-derived systems with smart sensing technologies, sustainable water-treatment frameworks, smart design, and life-cycle integration strategies, particularly for use in resource-constrained regions like Bangladesh and other globally impacted areas. Full article

(This article belongs to the Special Issue Advanced Nanomaterials for Water Remediation (2nd Edition))

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28 pages, 4683 KiB

Open AccessReview

A Comprehensive Overview of Co₃O₄ Nanoparticles: Solution Combustion Synthesis and Potential Applications

by Togzhan T. Mashan, Muhammad Hashami, Nurgul S. Bergeneva, Nurgul N. Nurmukhanbetova, Aigul S. Beisebayeva, Meruyert Nazhipkyzy, Gulnar U. Mamatova and Aigerim G. Zhaxybayeva

Nanomaterials 2025, 15(12), 932; https://doi.org/10.3390/nano15120932 - 16 Jun 2025

Viewed by 638

Abstract

Co₃O₄ nanoparticles synthesized by solution combustion synthesis present a versatile platform for the development of porous nanostructures with tunable morphology and physicochemical properties. Synthesis conditions and parameters such as fuel type; fuel-to-oxidizer ratio and temperature control lead yielding; and Co [...] Read more.

Co₃O₄ nanoparticles synthesized by solution combustion synthesis present a versatile platform for the development of porous nanostructures with tunable morphology and physicochemical properties. Synthesis conditions and parameters such as fuel type; fuel-to-oxidizer ratio and temperature control lead yielding; and Co₃O₄ NPs with fine particle size, surface area, and porosity result in enhancing their electrochemical and catalytic capabilities. This review evaluates present studies about SCS Co₃O₄ NPs to study how synthesis parameter modifications affect both surface morphology and material structure characteristics including porosity features, which make their improved performance ideal for lithium-ion batteries and supercapacitors. Moreover, the integration of dopants with carbon-based hybrid composites enhances material conductivity and stability by addressing both capacity fading and low electronic conductivity concerns. This review mainly aims to explore the significant relation between fundamental material design principles together with practical uses and provides predictions about future research advancements that aim to enhance the performance of Co₃O₄ NPs in next-generation energy and environmental technology applications. Full article

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

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15 pages, 1476 KiB

Open AccessArticle

The Facile Construction of Defect-Engineered and Surface-Modified UiO-66 MOFs for Promising Oxidative Desulfurization Performance

by Chao Wang, Junchao Ding, Haoyu Wu, Jiaxuan Zhang, Jing Xu, Ying Zhang, Mindan Ma, Ming Zhang and Hongping Li

Nanomaterials 2025, 15(12), 931; https://doi.org/10.3390/nano15120931 - 15 Jun 2025

Viewed by 286

Abstract

The effective and deep removal of unreactive sulfides to achieve ultra-low-sulfur or sulfur-free oils has recently attracted extensive attention. In this work, a series of UiO-66 based catalysts have been prepared facilely for the effective removal of unreactive sulfides. Here, the incorporation of [...] Read more.

The effective and deep removal of unreactive sulfides to achieve ultra-low-sulfur or sulfur-free oils has recently attracted extensive attention. In this work, a series of UiO-66 based catalysts have been prepared facilely for the effective removal of unreactive sulfides. Here, the incorporation of nitro functional groups into UiO-66, along with the construction of defects, results in remarkable sulfur removal for dibenzothiophene (DBT), achieving oil with sulfur content of less than 1 ppm. The successful construction of the designed catalysts was verified through a series of characterization studies. The exposed unsaturated metal sites help provide significantly more active reaction sites. In addition, the incorporated nitro group, with its electron-withdrawing property, would help increase the Lewis acidity of the catalytic metal sites. Thus, the catalytic oxidative capability of the designed UiO-66-based catalysts would be significantly increased. The enhanced catalytic oxidative performance helps ensure acceptable sulfur removal for oils with much higher sulfur concentrations. Additionally, the catalyst developed in this work can also be used to remove the derivatives of DBT with even lower reactivity. The relatively mild reaction conditions, combined with the exceptional sulfur removal, demonstrate the practicality of this reaction system. Full article

(This article belongs to the Section Inorganic Materials and Metal-Organic Frameworks)

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17 pages, 5557 KiB

Open AccessArticle

Synthesized Nano-Titanium Dioxide (Nano-TiO₂) via Ammonium Fluorotitanate ((NH₄)₂TiF₆) Precipitation with Ammonia Solution

by Yufeng Guo, Cong Zhou, Shuai Wang, Feng Chen, Yanqin Xie, Jinlai Zhang and Lingzhi Yang

Nanomaterials 2025, 15(12), 930; https://doi.org/10.3390/nano15120930 - 15 Jun 2025

Viewed by 245

Abstract

This study focuses on the chemical synthesis of nano-titanium dioxide (nano-TiO₂) via ammonium fluorotitanate ((NH₄)₂TiF₆) precipitation with ammonia solution, aiming to elucidate the effects of experimental parameters—including reaction temperature, duration, molar ratio of (NH₄ [...] Read more.

This study focuses on the chemical synthesis of nano-titanium dioxide (nano-TiO₂) via ammonium fluorotitanate ((NH₄)₂TiF₆) precipitation with ammonia solution, aiming to elucidate the effects of experimental parameters—including reaction temperature, duration, molar ratio of (NH₄)₂TiF₆ to ammonia, and (NH₄)₂TiF₆ concentration—on the particle size of synthesized nanoparticles, as well as the correlation between particle size and photocatalytic performance. The synthesized nanoparticles predominantly exhibited spindle-shaped morphology. Direct TEM imaging revealed the crystallization and growth mechanisms during synthesis: higher molar ratios, combined with lower temperatures and shorter durations, facilitated the formation of ultrafine particles, whereas lower molar ratios, with elevated temperatures and prolonged reaction times, yielded larger particles. Notably, nanorod structures emerged under low-temperature conditions with F⁻ ion adsorption. To investigate the relationship between particle size and photocatalytic performance, a Taguchi method-inspired experimental design was employed to evaluate the positive or negative impacts of particle size on photocatalytic activity. An experimental matrix was constructed using coded values for each factor, and regression coefficients were calculated to quantify input-output correlations. Results demonstrate that titanium dioxide catalysts with a particle size range of 50–75 nm exhibit optimal photocatalytic efficiency. Full article

(This article belongs to the Section Energy and Catalysis)

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41 pages, 7453 KiB

Open AccessReview

Recent Advances in Suspended 2D Materials and Their Applications

by Xuanshuo Zhang, Min Li, Qingya Wang, Yuxian Liang, Jing Wei, Hongbo Li and Fangze Liu

Nanomaterials 2025, 15(12), 929; https://doi.org/10.3390/nano15120929 - 15 Jun 2025

Viewed by 564

Abstract

Two-dimensional (2D) materials have attracted significant attention, owing to their atomically thin thickness; large specific surface area; and excellent mechanical, optical, and electronic properties. Suspended 2D materials, which eliminate substrate effects, exhibit unique potential in a variety of applications, including ultrasensitive sensors, flexible [...] Read more.

Two-dimensional (2D) materials have attracted significant attention, owing to their atomically thin thickness; large specific surface area; and excellent mechanical, optical, and electronic properties. Suspended 2D materials, which eliminate substrate effects, exhibit unique potential in a variety of applications, including ultrasensitive sensors, flexible electronic devices, acoustic devices, and optoelectronic devices. However, a central challenge in the fabrication of high-quality suspended structures lies in transfer technology—how to accurately transfer atomically thin layers onto target substrates or form self-suspended structures without introducing contamination or causing mechanical damage. This review summarizes recent advances in the fabrication, characterization, and applications of suspended 2D materials. We focus particularly on transfer methods, offering a comparative analysis of their advantages and limitations, and conclude with insights into future directions and remaining challenges. Full article

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

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15 pages, 1687 KiB

Open AccessArticle

Study on Regulation Mechanism of Heat Transport at Aluminum Nitride/Graphene/Silicon Carbide Heterogeneous Interface

by Dongjing Liu, Pengbo Wang, Zhiliang Hu, Jia Fu, Wei Qin, Jianbin Yu, Yangyang Zhang, Bing Yang and Yunqing Tang

Nanomaterials 2025, 15(12), 928; https://doi.org/10.3390/nano15120928 - 14 Jun 2025

Viewed by 236

Abstract

In order to solve the self-heating problem of power electronic devices, this paper adopts a nonequilibrium molecular dynamics approach to study the thermal transport regulation mechanism of the aluminum nitride/graphene/silicon carbide heterogeneous interface. The effects of temperature, size, and vacancy defects on interfacial [...] Read more.

In order to solve the self-heating problem of power electronic devices, this paper adopts a nonequilibrium molecular dynamics approach to study the thermal transport regulation mechanism of the aluminum nitride/graphene/silicon carbide heterogeneous interface. The effects of temperature, size, and vacancy defects on interfacial thermal conductivity are analyzed by phonon state density versus phonon participation rate to reveal their phonon transfer mechanisms during thermal transport. It is shown that the interfacial thermal conductance (ITC) increases about three times when the temperature increases from 300 K to 1100 K. It is analyzed that the increase in temperature will enhance lattice vibration, enhance phonon coupling degree, and thus increase its ITC. With the increase in the number of AlN-SiC layers from 8 to 28, the ITC increases by about 295.3%, and it is analyzed that the increase in the number of AlN-SiC layers effectively reduces the interfacial scattering and improves the phonon interfacial transmission efficiency. The increase in the number of graphene layers from 1 layer to 4 layers decreases the ITC by 70.3%. The interfacial thermal conductivity reaches a minimum, which is attributed to the increase in graphene layers aggravating the degree of phonon localization. Under the influence of the increase in graphene single and double vacancy defects concentration, the ITC is slightly reduced. When the defect rate reaches about 20%, the interfacial thermal conductance of SV (single vacancy) and DV (double vacancy) defects rises back to 5.606 × 10⁻² GW/m²K and 5.224 × 10⁻² GW/m²K, respectively. It is analyzed that the phonon overlapping and the participation rate act at the same time, so the heat-transferring phonons increase, increasing the thermal conductance of their interfaces. The findings provide theoretical support for optimizing the thermal management performance of heterostructure interfaces. Full article

(This article belongs to the Special Issue Advanced Nanostructures in Thermal Engineering: Design, Fabrication and Application)

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16 pages, 5821 KiB

Open AccessArticle

Synthesis, Characterization, and Toxicity Evaluation of Size-Dependent Iron-Based Metal–Organic Frameworks

by Zhang Liu, Huaiyu Deng, Yuanzhi Zheng, Yuan Tian, Yanting Zhang, Renz Marion Garcia, Sheena Anne Henson Garcia and King Lun Yeung

Nanomaterials 2025, 15(12), 927; https://doi.org/10.3390/nano15120927 - 14 Jun 2025

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Abstract

Iron-based metal–organic frameworks (Fe-MOFs) are promising for biomedical and environmental applications due to their porosity, tunable chemistry, and biocompatibility. This study examines how particle size, morphology, and ligand composition affect the properties and cytotoxicity of MIL-101(Fe) and MIL-88A. MIL-101(Fe) (octahedral) and MIL-88A (rod-like) [...] Read more.

Iron-based metal–organic frameworks (Fe-MOFs) are promising for biomedical and environmental applications due to their porosity, tunable chemistry, and biocompatibility. This study examines how particle size, morphology, and ligand composition affect the properties and cytotoxicity of MIL-101(Fe) and MIL-88A. MIL-101(Fe) (octahedral) and MIL-88A (rod-like) were synthesized with a controlled size (~200 nm to ~5 μm). Both showed a high crystallinity and stability. Cytotoxicity assays in A549 cells revealed size- and structure-dependent effects: smaller particles of MIL-88A caused greater toxicity (32.5% viability) than MIL-101(Fe) (66.1% viability at 100 μg/mL), while larger particles were less toxic. MIL-88A also induced higher reactive oxidative species (ROS) levels and degraded more rapidly, releasing more Fe ions. Toxicity predication analysis indicated the higher inherent toxicity of MIL-88A’s ligand (fumaric acid) compared to MIL-101(Fe)’s terephthalic acid. These results demonstrate that structural and chemical factors collectively influence Fe-MOFs’ biocompatibility and highlight the importance of rational design for safer MOF applications. Full article

(This article belongs to the Special Issue Safety and Toxicity of Carbon Nanotubes, Nanoparticles and Other Nanomaterials: 2nd Edition)

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12 pages, 918 KiB

Open AccessArticle

TiO₂ Nanoparticles Loaded with Polygonum cuspidatum Extract for Wound Healing Applications: Exploring Their Hemolytic, Antioxidant, Cytotoxic, and Antimicrobial Properties

by Gabriela Fletes-Vargas, Rogelio Rodríguez-Rodríguez, Natalha Vicentina Pinto, Kelly Cristina Kato, Guilherme Carneiro, Ana Paula Rodrigues, Helen Rodrigues-Martins and Hugo Espinosa-Andrews

Nanomaterials 2025, 15(12), 926; https://doi.org/10.3390/nano15120926 - 14 Jun 2025

Viewed by 257

Abstract

The dry roots of Polygonum cuspidatum contain resveratrol, a compound known for its antimicrobial and protective effects against oxidative stress, which is associated with impaired wound healing. In this study, titanium dioxide nanoparticles (TiO₂NPs) were loaded with a P. cuspidatum extract [...] Read more.

The dry roots of Polygonum cuspidatum contain resveratrol, a compound known for its antimicrobial and protective effects against oxidative stress, which is associated with impaired wound healing. In this study, titanium dioxide nanoparticles (TiO₂NPs) were loaded with a P. cuspidatum extract (TiO₂-loaded extract NPs), and the resveratrol release profile, hemocompatibility, antioxidant, cytotoxic, and antimicrobial activities were evaluated. The results demonstrated that TiO₂-loaded extract NPs exhibited antioxidant activity for DPPH (Inhibitory Concentration 50 (IC₅₀) = 62.31 mg Trolox Equivalent (TE)/mL) and ABTS⁺ (IC₅₀ = 4.8 mg TE/mL) assays, along with suitable hemocompatibility (3.02% at 10 mg/mL), in comparison with bulk TiO₂ NPs. Additionally, temperature influenced the resveratrol release over time. The P. cuspidatum extract alone showed strong antibacterial activity, with a Minimal Inhibitory Concentration (MIC) of 5 µg/mL, TiO₂-loaded extract NPs showed MIC values about 50 mg/mL, while bulk TiO₂ NPs exhibited no antibacterial effect against the tested strains. In contrast, the P. cuspidatum extract, the TiO₂-loaded extract NPs, and the bulk TiO₂ NPs did not demonstrate antifungal activity against Candida albicans and C. glabrata. Moreover, TiO₂-loaded extract NPs showed no cytotoxicity against the L-929 cell line at concentrations ranging from 1.5 to 150 µg/mL, unlike TiO₂ NPs, which exhibited high cytotoxic concentrations between 9.4 and 300 µg/mL. These findings suggest that TiO₂-loaded extract NPs effectively control the release of resveratrol and hold promises for applications in skin management and wound healing. Full article

(This article belongs to the Special Issue Applications of Functional Nanomaterials in Biomedical Science)

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13 pages, 2786 KiB

Open AccessArticle

Effect of Cu Doping on Synthesis, Composition and Sensor Properties of In₂O₃ Nanostructures

by Mariya I. Ikim, Elena Yu. Spiridonova, Olusegun Johnson Ilegbusi and Leonid I. Trakhtenberg

Nanomaterials 2025, 15(12), 925; https://doi.org/10.3390/nano15120925 - 14 Jun 2025

Viewed by 226

Abstract

Cu-doped In₂O₃ nanocomposites with copper compositions of 1–3 wt.% are synthesized by a hydrothermal method using water or alcohol as a solvent. Cubic In₂O₃ is formed when water is used for synthesis, while composites synthesized in alcohol [...] Read more.

Cu-doped In₂O₃ nanocomposites with copper compositions of 1–3 wt.% are synthesized by a hydrothermal method using water or alcohol as a solvent. Cubic In₂O₃ is formed when water is used for synthesis, while composites synthesized in alcohol contain rhombohedral In₂O₃. This trend is independent of the amount of copper introduced. The Cu ions are shown to be uniformly distributed in the In₂O₃ nanoparticles without significant destruction of the indium oxide structure. All the composites exhibit a porous structure that depends on the solvent used for the synthesis. The addition of copper to both crystalline forms of indium oxide increases the resistance of the films and reduces the operating temperature. The phase state of indium oxide also affects the conductivity of the composites. There is an increase in sensory response to H₂ and CO with the introduction of Cu into samples with cubic structure, but a reduction in response in samples with the rhombohedral phase of indium oxide. Full article

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

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11 pages, 7517 KiB

Open AccessArticle

Effect of Size on Phase Mixing Patterns in Rapidly Solidified Au–Ge Nanoparticles

by Olha Khshanovska, Vladyslav Ovsynskyi and Aleksandr Kryshtal

Nanomaterials 2025, 15(12), 924; https://doi.org/10.3390/nano15120924 - 14 Jun 2025

Viewed by 221

Abstract

We investigated the morphological patterns, crystalline structures and their thermal stability in solidified Au–Ge nanoparticles ranging in size from 10 to 500 nm. Liquid Au–Ge alloy nanoparticles with hypoeutectic composition were rapidly cooled from a temperature of 500 °C in a TEM and [...] Read more.

We investigated the morphological patterns, crystalline structures and their thermal stability in solidified Au–Ge nanoparticles ranging in size from 10 to 500 nm. Liquid Au–Ge alloy nanoparticles with hypoeutectic composition were rapidly cooled from a temperature of 500 °C in a TEM and characterized using advanced TEM techniques. We demonstrated that Au–Ge nanoparticles 10–80 nm in size predominantly solidified into a Janus-like morphology with nearly pure single-crystalline hcp Au and diamond cubic Ge domains. These particles remained stable up to the eutectic temperature, indicating that Ge doping and particle size play key roles in stabilizing the hcp Au phase. In turn, larger nanoparticles exhibited a metastable core–shell morphology with polycrystalline Ge shell and hcp Au-Ge alloy core under solidification. It was shown that the mentioned morphology and crystalline structure evolved into the equilibrium Janus morphology with fcc Au and diamond Ge domains at temperatures above ≈160 °C. Full article

(This article belongs to the Special Issue Nanoscale Microscopy Techniques for Energy Materials)

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12 pages, 4386 KiB

Open AccessArticle

TiO₂ Nanorod Array for Betavoltaic Cells: Performance Validation and Enhancement with Electron Beam and ⁶³Ni Irradiations

by Sijie Li, Tongxin Jiang, Yu Cao, Wendi Zhao, Haisheng San, Xue Li, Lifeng Zhang and Xin Li

Nanomaterials 2025, 15(12), 923; https://doi.org/10.3390/nano15120923 - 14 Jun 2025

Viewed by 218

Abstract

The growing demand for reliable micropower sources in extreme environments has accelerated the development of betavoltaic cells (BV cells) with high energy conversion efficiency and superior radiation resistance. This study demonstrates an advanced BV cell architecture utilizing three-dimensional TiO₂ nanorod arrays (TNRAs) [...] Read more.

The growing demand for reliable micropower sources in extreme environments has accelerated the development of betavoltaic cells (BV cells) with high energy conversion efficiency and superior radiation resistance. This study demonstrates an advanced BV cell architecture utilizing three-dimensional TiO₂ nanorod arrays (TNRAs) integrated with a NiO_x hole transport layer (HTL). Monte Carlo simulations were employed to optimize the cell design and determine the fabrication parameters for growing TNRAs on FTO substrates via hydrothermal synthesis. The performance evaluation employed both electron beam (2.36 × 10⁹ e/cm²·s) and ⁶³Ni (3.4 mCi/cm²) irradiation methods. The simulation results revealed optimal energy deposition characteristics, with ~96% of β-particle energy effectively absorbed within the 2 μm thick FTO/TNRA/NiO_x/Au structure. The NiO_x-incorporated device achieved an energy conversion efficiency of 4.84%, with a short-circuit current of 119.9 nA, an open-circuit voltage of 324.2 mV, and a maximum power output of 24.0 nW, representing a 3.76-fold enhancement over HTL-free devices. Radioactive source testing confirmed stable power generation and linear efficiency scaling, validating electron beam irradiation as an effective accelerated testing methodology for BV cell research. Full article

(This article belongs to the Section Energy and Catalysis)

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