Materials

17 pages, 1599 KB

Open AccessEditor’s ChoiceArticle

New Biodegradable Carboxymethyl Cellulose-Based Films with Liquid Products of Wood Pine Pyrolysis with Antibacterial and Antioxidant Properties

by Grażyna B. Dąbrowska, Marcel Antoszewski, Aleksandra Szydłowska-Czerniak, Aneta Raszkowska-Kaczor, Tomasz Jędrzejewski, Sylwia Wrotek, Monika Bartkowiak, Maria Swiontek Brzezinska and Magdalena Zborowska

Materials 2025, 18(10), 2228; https://doi.org/10.3390/ma18102228 - 12 May 2025

Viewed by 1129

Abstract

Novel carboxymethylcellulose (CMC) films with liquid products of pyrolysis (LPP) from wood pine were produced. The obtained CMC-LPP films were plasticized with 5% glycerol. CMC-LPP films were a light brown colour with a characteristic smoky scent, and showed a higher oxygen permeability when [...] Read more.

Novel carboxymethylcellulose (CMC) films with liquid products of pyrolysis (LPP) from wood pine were produced. The obtained CMC-LPP films were plasticized with 5% glycerol. CMC-LPP films were a light brown colour with a characteristic smoky scent, and showed a higher oxygen permeability when compared to control film without the addition of the LPP. CMC-LPP exhibited high antioxidant activity (5 and 18 times higher than CMC films). Furthermore, the antibacterial activity of the CMC-LPP films was tested, showing a strong inhibiting growth effect on the seven tested human pathogenic bacteria. The new material had the most substantial bacteriostatic effect on Listeria monocytogenes, Salmonella typhimurium, and Pseudomonas aeruginosa. Introduction of LPP to plasticised CMC produces an eco-friendly material with biocidal effect and favourable mechanical and structural properties, which shows its potential for possible use in many industries. Full article

(This article belongs to the Special Issue Multi-Scale Bionic Materials: Interfacial Design, Effective Fabrication and Functional Application)

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13 pages, 2728 KB

Open AccessEditor’s ChoiceArticle

Machine Learning-Assisted Discovery of Empirical Rule for Martensite Transition Temperature of Shape Memory Alloys

by Hao-Xuan Liu, Hai-Le Yan, Nan Jia, Bo Yang, Zongbin Li, Xiang Zhao and Liang Zuo

Materials 2025, 18(10), 2226; https://doi.org/10.3390/ma18102226 - 12 May 2025

Viewed by 990

Abstract

Shape memory alloys (SMAs) derive their unique functional properties from martensitic transformations, with the martensitic transformation temperature (T_M) serving as a key design parameter. However, existing empirical rules, such as the valence electron concentration (VEC) and lattice volume (V) criteria, [...] Read more.

Shape memory alloys (SMAs) derive their unique functional properties from martensitic transformations, with the martensitic transformation temperature (T_M) serving as a key design parameter. However, existing empirical rules, such as the valence electron concentration (VEC) and lattice volume (V) criteria, are typically restricted to specific alloy families and lack general applicability. In this work, we used a data-driven methodology to find a generalizable empirical formula for T_M in SMAs by combining high-throughput first-principles calculations, feature engineering, and symbol regression techniques. Key factors influencing T_M were first identified and a predictive machine learning model was subsequently trained based on these features. Furthermore, an empirical formula of T_M =

82 (\bar{ρ} \cdot \bar{M P}) - 700

was derived, where

\bar{ρ}

and

\bar{M P}

represent the weight-average value of density and melting point, respectively. The empirical formula exhibits strong generalizability across a wide range of SMAs, such as NiMn-based, NiTi-based, TiPt-based, and AuCd-based SMAs, etc., offering practical guidance for the compositional design and optimization of shape memory alloys. Full article

(This article belongs to the Special Issue Magnetic Shape Memory Alloys: Fundamentals and Applications)

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15 pages, 3410 KB

Open AccessEditor’s ChoiceArticle

CeO₂-Modified Ni₂P/Fe₂P as Efficient Bifunctional Electrocatalyst for Water Splitting

by Xinyang Wu, Dandan Wang, Yongpeng Ren, Haiwen Zhang, Shengyu Yin, Ming Yan, Yaru Li and Shizhong Wei

Materials 2025, 18(10), 2221; https://doi.org/10.3390/ma18102221 - 11 May 2025

Viewed by 1601

Abstract

Developing efficient bifunctional electrocatalysts with excellent stability at high current densities for overall water splitting is a challenging yet essential objective. However, transition metal phosphides encounter issues such as poor dispersibility, low specific surface area, and limited electronic conductivity, which hinder the achievement [...] Read more.

Developing efficient bifunctional electrocatalysts with excellent stability at high current densities for overall water splitting is a challenging yet essential objective. However, transition metal phosphides encounter issues such as poor dispersibility, low specific surface area, and limited electronic conductivity, which hinder the achievement of satisfactory performance. Therefore, this study presents the highly efficient bifunctional electrocatalyst of CeO₂-modified NiFe phosphide on nickel foam (CeO₂/Ni₂P/Fe₂P/NF). Ni₂P/Fe₂P coupled with CeO₂ was deposited on nickel foam through hydrothermal synthesis and sequential calcination processes. The electrocatalytic performance of the catalyst was evaluated in an alkaline solution, and it exhibited an HER overpotential of 87 mV at the current density of 10 mA cm⁻² and an OER overpotential of 228 mV at the current density of 150 mA cm⁻². Furthermore, the catalyst demonstrated good stability, with a retention rate of 91.2% for the HER and 97.3% for the OER after 160 h of stability tests. The excellent electrochemical performance can be attributed to the following factors: (1) The interface between Ni₂P/Fe₂P and CeO₂ facilitates electron transfer and reactant adsorption, thereby improving catalytic activity. (2) The three-dimensional porous structure of nickel foam provides an ideal substrate for the uniform distribution of Ni₂P, Fe₂P, and CeO₂ nanoparticles, while its high conductivity facilitates electron transport. (3) The incorporation of larger Ce³⁺ ions in place of smaller Fe³⁺ ions leads to lattice distortion and an increase in defects within the NiFe-layered double hydroxide structure, significantly enhancing its catalytic performance. This research finding offers an effective strategy for the design and synthesis of low-cost, high-potential catalysts for water electrolysis. Full article

(This article belongs to the Section Catalytic Materials)

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22 pages, 15055 KB

Open AccessEditor’s ChoiceArticle

Tension Strength of Multi-Fastener, Single-Lap Joints in Flax and Jute Composite Plates Using Bolts or Rivets

by Mike R. Bambach

Materials 2025, 18(10), 2180; https://doi.org/10.3390/ma18102180 - 8 May 2025

Cited by 2 | Viewed by 654

Abstract

The behavior of joints and fasteners in fiber-epoxy composites has been researched for several decades, and many studies have demonstrated their performance in tension testing. These studies have focused nearly exclusively on synthetic fibers, such as carbon and glass. Meanwhile, natural fiber–epoxy composites [...] Read more.

The behavior of joints and fasteners in fiber-epoxy composites has been researched for several decades, and many studies have demonstrated their performance in tension testing. These studies have focused nearly exclusively on synthetic fibers, such as carbon and glass. Meanwhile, natural fiber–epoxy composites have recently received considerable attention as load-bearing members, including as columns and beams. In order for individual members to be used to create structural systems, the behavior of mechanically fastened joints in natural fiber–epoxy composites needs to be thoroughly investigated. This paper presents an experimental program of 120 single-lap joints in flax–epoxy and jute–epoxy composites. Between one and three mechanical fasteners were used in the joints, and both bolts and rivets were investigated. A variety of geometric variables were investigated, relevant to joints between load-bearing members. The results are used to demonstrate the optimum strength of multi-fastener joints in natural fiber composite structural systems. It is shown that maximum joint efficiency is achieved with larger fastener-diameter-to-width ratios, three fasteners (located along the line of action of the force), and edge-distance-to-fastener-diameter ratios greater than 2.5. Full article

(This article belongs to the Special Issue Structure, Properties and Applications of Nanocomposites and Polymer Based Materials)

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16 pages, 3292 KB

Open AccessEditor’s ChoiceArticle

Topology Optimization of Additively Manufactured Adherends for Increased Adhesive Bond Strength

by Michael Ascher and Ralf Späth

Materials 2025, 18(10), 2170; https://doi.org/10.3390/ma18102170 - 8 May 2025

Cited by 2 | Viewed by 774

Abstract

The limited build space of additive manufacturing (AM) machines constrains the maximum size of AM components, while manufacturing costs rise with geometric complexity. To enhance value and overcome size limitations, it can be more efficient to join non-AM and AM components to meet [...] Read more.

The limited build space of additive manufacturing (AM) machines constrains the maximum size of AM components, while manufacturing costs rise with geometric complexity. To enhance value and overcome size limitations, it can be more efficient to join non-AM and AM components to meet the requirements by means of a hybrid structure. Adhesive bonding is particularly suitable for such joints, as it imposes no constraints on the joining surface’s geometry or the adherend’s material. To ensure structural integrity, it is conceivable to exploit the design freedom underlying AM processes by optimizing the topology of the AM component to stress the adhesive layer homogeneously. This study explores the feasibility of this concept using the example of an axially loaded single-lap tubular joint between a carbon fiber-reinforced composite tube and an additively manufactured laser-based powder-bed-fusion aluminum alloy sleeve. The sleeve topology was optimized using the finite element method, achieving a

75 % P

reduction in adhesive stress increase compared to a non-optimized sleeve. Due to the pronounced ductility of the two-component epoxy-based adhesive, the static bond strength remained unaffected, whereas fatigue life significantly improved. The findings demonstrate the feasibility of leveraging AM design freedom to enhance adhesive joint performance, providing a promising approach for hybrid structures in lightweight applications. Full article

(This article belongs to the Special Issue Advances in the Experimentation and Numerical Modeling of Material Joining Processes (Second Edition))

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24 pages, 2746 KB

Open AccessEditor’s ChoiceReview

Molecularly Imprinted Titanium Dioxide: Synthesis Strategies and Applications in Photocatalytic Degradation of Antibiotics from Marine Wastewater: A Review

by Xue Han, Yu Jin, Luyang Zhao, Yuying Zhang, Binqiao Ren, Xiaoxiao Song and Rui Liu

Materials 2025, 18(9), 2161; https://doi.org/10.3390/ma18092161 - 7 May 2025

Cited by 3 | Viewed by 1069

Abstract

Antibiotic residues in the marine environment pose a serious threat to ecosystems and human health, and there is an urgent need to develop efficient and selective pollution control technologies. Molecular imprinting technology (MIT) provides a new idea for antibiotic pollution control with its [...] Read more.

Antibiotic residues in the marine environment pose a serious threat to ecosystems and human health, and there is an urgent need to develop efficient and selective pollution control technologies. Molecular imprinting technology (MIT) provides a new idea for antibiotic pollution control with its specific recognition and targeted removal ability. However, traditional titanium dioxide (TiO₂) photocatalysts have limited degradation efficiency and lack of selectivity for low concentrations of antibiotics. This paper reviews the preparation strategy and modification means of molecularly imprinted TiO₂ (MI-TiO₂) and its composites and systematically explores its application mechanism and performance advantages in marine antibiotic wastewater treatment. It was shown that MI-TiO₂ significantly enhanced the selective degradation efficiency of antibiotics such as tetracyclines and sulfonamides through the enrichment of target pollutants by specifically imprinted cavities, combined with the efficient generation of photocatalytic reactive oxygen species (ROS). In addition, emerging technologies such as magnetic/electric field-assisted catalysis and photothermal synergistic effect further optimized the recoverability and stability of the catalysts. This paper provides theoretical support for the practical application of MI-TiO₂ in complex marine pollution systems and looks forward to its future development in the field of environmental remediation. Full article

(This article belongs to the Section Catalytic Materials)

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12 pages, 2540 KB

Open AccessEditor’s ChoiceArticle

Monolithic GaN-Based Dual-Quantum-Well LEDs with Size-Controlled Color-Tunable White-Light Emission

by Seung Hun Lee, Dabin Jeon, Gun-Woo Lee and Sung-Nam Lee

Materials 2025, 18(9), 2140; https://doi.org/10.3390/ma18092140 - 6 May 2025

Viewed by 933

Abstract

We report a monolithic GaN-based light-emitting diode (LED) platform capable of color-tunable white-light emission via LED size scaling. By varying the LED size from 800 µm to 50 µm, the injection current density was effectively controlled under constant driving current, enabling precise modulation [...] Read more.

We report a monolithic GaN-based light-emitting diode (LED) platform capable of color-tunable white-light emission via LED size scaling. By varying the LED size from 800 µm to 50 µm, the injection current density was effectively controlled under constant driving current, enabling precise modulation of carrier distribution within a dual-composition multi-quantum well (MQW) structure. The active layer consists of five lower In_0.15Ga_0.85N/GaN QWs for blue emission and strain induction, and an upper In_0.3Ga_0.7N/GaN single QW engineered for red-orange emission. The strain imposed by lower QWs promotes indium segregation in the last QW through spinodal decomposition, resulting in a broadened emission spanning from ~500 nm to 580 nm. High-resolution TEM and EDX analyses directly confirmed the indium segregation and phase-separated structure of the last QW. Spectral analysis revealed that larger devices exhibited dominant emission at 580 nm with a correlated color temperature (CCT) of 2536 K and a CIE coordinate of (0.501, 0.490). As LED size decreased, increased hole injection allowed recombination to occur in deeper QWs, resulting in a blueshift to 450 nm and a CCT of 9425 K with CIE (0.224, 0.218) in the 50 × 50 µm² LED. This approach enables phosphor-free white-light generation with tunable color temperatures and chromaticities using a single wafer, offering a promising strategy for compact, adaptive solid-state lighting applications. Full article

(This article belongs to the Special Issue Advances in Nanophotonic Materials, Devices, and Applications)

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19 pages, 9507 KB

Open AccessEditor’s ChoiceArticle

Mechanical Strength of Waste Materials: A Cone Penetration Testing-Based Geotechnical Assessment for the Reclamation of Landfills

by Marek Bajda, Mariusz Lech, Katarzyna Markowska-Lech, Piotr Osiński and Eugeniusz Koda

Materials 2025, 18(9), 2130; https://doi.org/10.3390/ma18092130 - 6 May 2025

Viewed by 806

Abstract

The stability and mechanical properties of municipal solid waste (MSW) deposits in closed landfills are critical for safe land reclamation and infrastructure development. This study employs Cone Penetration Testing (CPT) to evaluate the geotechnical parameters of aged waste at three closed landfill sites [...] Read more.

The stability and mechanical properties of municipal solid waste (MSW) deposits in closed landfills are critical for safe land reclamation and infrastructure development. This study employs Cone Penetration Testing (CPT) to evaluate the geotechnical parameters of aged waste at three closed landfill sites in central Poland. Key parameters, including shear strength, internal friction angle, density, and liquidity index, were assessed to determine slope stability and bearing capacity for future redevelopment. Due to the heterogeneous nature of MSW, CPT results were analyzed in conjunction with empirical correlations and nomograms to improve accuracy, so the parameters can be used for future numerical modeling and proposing new computational approaches for landfill body elastic and mechanical behavior predictions. The findings indicate significant variability in landfill waste mechanical properties, influenced by waste composition, decomposition stage, and compaction history. The study highlights CPT’s reliable detremination of geotechnical parameters for landfill restoration projects, particularly for infrastructure, creating the potential for green energy and sustainable development. The results contribute to improving engineering practices in landfill restoration and ensuring the long-term stability of post-closure land use. This study also contributes to obtaining reliable results on anthropogenic waste material mechanical parameters at both the material point and at the overall structural scale, benefiting future computational methods and modeling approaches for analyzing structural and geotechnical safety of such complex and demanding structures as landfills. Full article

(This article belongs to the Special Issue Computational and Experimental Methodologies for Advanced and Sustainable Structural Materials)

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23 pages, 4075 KB

Open AccessEditor’s ChoiceArticle

CD44 Receptor-Mediated Ferroptosis Induction by Hyaluronic Acid Carbon Quantum Dots in Triple-Negative Breast Cancer Cells Through Downregulation of SLC7A11 Pathway

by Karthikeyan Chandrasekaran, Chae Eun Lee, Seojeong Yun, Ashok Kumar Jangid, Sungjun Kim and Kyobum Kim

Materials 2025, 18(9), 2139; https://doi.org/10.3390/ma18092139 - 6 May 2025

Cited by 2 | Viewed by 1869

Abstract

The field of cancer therapy is actively pursuing highly effective self-targeted drug delivery materials endowed with exceptional properties. Recently, hyaluronic acid (HA), a naturally occurring polysaccharide, has been recognized as a potential target ligand for CD44 receptors, which are frequently expressed on various [...] Read more.

The field of cancer therapy is actively pursuing highly effective self-targeted drug delivery materials endowed with exceptional properties. Recently, hyaluronic acid (HA), a naturally occurring polysaccharide, has been recognized as a potential target ligand for CD44 receptors, which are frequently expressed on various solid tumor cells targeted in cancer therapy. HA carbon quantum dots (CQDs) exhibit several advantageous properties, including a high surface area-to-volume ratio, small particle size, biocompatibility, and low cytotoxicity, making them ideal for biomedical applications, such as CD44-targeted drug delivery in ferroptosis-based cancer therapy. In this study, we synthesized HA-CQDs to enhance CD44-mediated ligand–receptor interactions targeting triple-negative breast cancer (TNBC). CQDs facilitate the intracellular generation of reactive oxygen species (ROS), leading to glutathione depletion. These processes result in crucial actions such as the downregulation of glutathione peroxidase 4, downregulation of solute carrier family 7 member 11, and inhibition of cystine intake. The subsequent intracellular ROS, originating from lipid peroxidation, induces ferroptosis. Our HA-CQDs engage CD44 receptors, selectively targeting TNBCs and enhancing cancer recognition. This interaction potentially enhances the nanoplatform-based CD44 targeted therapeutic effects in inducing ferroptosis. Full article

(This article belongs to the Special Issue Functional Polymers for Energy, Biomedical and Electrical Applications)

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13 pages, 4450 KB

Open AccessEditor’s ChoiceArticle

Emergent Magnetic Order in Superconducting FeS Induced by Trace Cr Doping

by Yangzhou Wang, Qianshuo Wang, Yanhao Dong, Jin Wang, Shu Chen, Zihan Wang, Fei Chen, Guixin Cao, Wei Ren, Jie Li and Wen Wan

Materials 2025, 18(9), 2108; https://doi.org/10.3390/ma18092108 - 4 May 2025

Viewed by 712

Abstract

Multiband and nodal-like superconductivity (SC) with s- + d-wave pairing symmetry have implied that tetragonal iron sulphide (FeS) is a distinctive testbed for exploring unexpected electronic correlations. In particular, the low-moment disordered static magnetism originating from the Fe moment leads to the possibility [...] Read more.

Multiband and nodal-like superconductivity (SC) with s- + d-wave pairing symmetry have implied that tetragonal iron sulphide (FeS) is a distinctive testbed for exploring unexpected electronic correlations. In particular, the low-moment disordered static magnetism originating from the Fe moment leads to the possibility of the coexistence of magnetic orders (MOs) in the superconducting ground state via the tuning of electronic configurations. Here, guided by density functional theory (DFT) calculations, we found that slightly substitutionally doped chromium (Cr) atoms in tetragonal FeS single crystals can induce both considerable d-orbital reconstruction around the Fermi surface and a local magnetic moment of 2.4 µ_B at each doping site, which could highly modulate the SC ground states of the host. On this basis, a clear magnetic transition and reduced anisotropy of SC were experimentally observed. In particular, SC can survive with a doping content below 0.05. This coexistence of SC and MOs suggests strong spin correlations between Cr dopants and the host through exchange coupling. Further, an electronic temperature-related phase diagram of FeS with Cr doping contents from 0 to 0.07 is also provided. These results demonstrate that the continuous injection of local moments can be a controllable method to use to tune collective orders in unconventional iron-based superconductors. Full article

(This article belongs to the Section Quantum Materials)

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18 pages, 4516 KB

Open AccessEditor’s ChoiceArticle

Fabrication and Optoelectronic Properties of Advanced Quinary Amorphous Oxide Semiconductor InGaZnSnO Thin Film

by Hongyu Wu, Liang Fang, Zhiyi Li, Fang Wu, Shufang Zhang, Gaobin Liu, Hong Zhang, Wanjun Li and Wenlin Feng

Materials 2025, 18(9), 2090; https://doi.org/10.3390/ma18092090 - 2 May 2025

Viewed by 830

Abstract

As the typical representative of amorphous oxide semiconductors (AOS), quaternary indium gallium zinc oxide (IGZO) has been applied as the active layer of thin-film transistors (TFTs), but their mobility is still low (usually ~10 cm²/Vs). IGTO is reported to have larger [...] Read more.

As the typical representative of amorphous oxide semiconductors (AOS), quaternary indium gallium zinc oxide (IGZO) has been applied as the active layer of thin-film transistors (TFTs), but their mobility is still low (usually ~10 cm²/Vs). IGTO is reported to have larger mobility owing to the addition of Tin (Sn) in IZO. So, whether Sn doping can increase the optoelectronic properties of IGZO is a new topic worth studying. In this study, four series of quinary InGaZnSnO (IGZTO) oxide thin films were deposited on glass substrates using a high-purity IGZTO (In:Ga:Zn:Sn:O = 1:0.5:1.5:0.25:x, atomic ratio) ceramic target by RF magnetron sputtering. The effects of fabrication parameters (sputtering power, argon gas flow, and target-to-substrate distance) and film thickness on the microstructure, optical, and electrical properties of IGZTO thin films were investigated. The results show that all IGZTO thin films deposited at room temperature (RT) are amorphous and have a smooth and uniform surface with a low roughness (RMS of 0.441 nm, RA of 0.332 nm). They exhibit good average visible light transmittance (89.02~90.69%) and an optical bandgap of 3.47~3.56 eV. When the sputtering power is 90 W, the argon gas flow rate is 50 sccm, and the target-to-substrate distance is 60 mm, the IGZTO films demonstrate optimal electrical properties: carrier concentration (3.66 × 10¹⁹ cm⁻³), Hall mobility (29.91 cm²/Vs), and resistivity (0.54 × 10⁻² Ω·cm). These results provide a valuable reference for the property modulation of IGZTO films and the potential application in optoelectronic devices such as TFTs. Full article

(This article belongs to the Special Issue The Microstructures and Advanced Functional Properties of Thin Films)

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28 pages, 9329 KB

Open AccessEditor’s ChoiceArticle

Evaluating the Chemical Resistance and Performance of Thermochromic Polymers for Food Packaging

by Colette Breheny, Declan Mary Colbert, Gilberto Bezerra, Joseph Geever and Luke M. Geever

Materials 2025, 18(9), 2085; https://doi.org/10.3390/ma18092085 - 1 May 2025

Cited by 1 | Viewed by 1072

Abstract

The use of thermochromic pigments in food packaging offers several advantages, including improved food safety, waste reduction, and temperature change monitoring. However, little is known about how chemically resilient these materials are, especially regarding optical stability, thermochromic activation, and mechanical integrity following exposure [...] Read more.

The use of thermochromic pigments in food packaging offers several advantages, including improved food safety, waste reduction, and temperature change monitoring. However, little is known about how chemically resilient these materials are, especially regarding optical stability, thermochromic activation, and mechanical integrity following exposure to acidic, alkaline, oil-based, and neutral food-contact environments. This study evaluates the chemical resistance, thermal cycling effects, and mechanical durability of thermochromic pigment–polymer blends. Thermochromic polymer samples were subjected to multiple chemical environments, repeated thermal cycling, and mechanical analysis to assess degradation behavior. The findings show that virgin food-grade polymer with no thermochromic pigment sustains its performance stability throughout chemical exposure with little degradation. However, thermochromic polymer blends experienced reduced thermochromic functionality. This study offers insight into how well thermochromic pigment can be incorporated into intelligent food packaging despite the limitations associated with chemical exposure. Full article

(This article belongs to the Section Smart Materials)

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18 pages, 4602 KB

Open AccessEditor’s ChoiceArticle

Effect of the Peri-Annulated Dichalcogenide Bridge on the Bipolar Character of Naphthalimide Derivatives Used as Organic Electrode Materials

by Delyana Marinova, Lyuben Borislavov, Silva Stanchovska, Konstantin Konstantinov, Monika Mutovska, Stanimir Stoyanov, Yulian Zagranyarski, Yanislav Danchovski, Hristo Rasheev, Alia Tadjer and Radostina Stoyanova

Materials 2025, 18(9), 2066; https://doi.org/10.3390/ma18092066 - 30 Apr 2025

Viewed by 943

Abstract

In recent years, bipolar organic electrode materials have gained recognition as competitive alternatives to inorganic materials due to their unique multielectron redox mechanism for energy storage. In this study, we examined the mechanism of redox reactions in naphthalimide (NI) derivatives when used as [...] Read more.

In recent years, bipolar organic electrode materials have gained recognition as competitive alternatives to inorganic materials due to their unique multielectron redox mechanism for energy storage. In this study, we examined the mechanism of redox reactions in naphthalimide (NI) derivatives when used as electrodes in lithium half-cells with ionic liquid electrolytes. The NI derivatives consist of three building fragments: an aromatic naphthalene core, N-alkylated imide unit, and a peri-dichalcogenide bridge. The integration of electrochemical and microscopic methods with DFT calculations facilitates the delineation of the role of each fragment in the oxidation and reduction reactions of NI derivatives. It is found that the peri-dichalcogenide bridge is mainly involved in the oxidation of NI derivatives above 3.9 V, the charge compensation being achieved by electrolyte TFSI⁻ counter-ions. The reduction of NI derivatives with two Li⁺ ions is mainly due to the participation of the chalcogenide bridge, while after interaction with the next two Li⁺ ions, the imide fragment and the naphthalene moiety contribute equally to the reduction. Based on the leading role of the peri-dichalcogenide bridge, the redox properties of NI derivatives are effectively controlled by the gradual replacement of S with Se and Te atoms in the bridge. To improve the electronic conductivity of NIs, composites with rGO are also synthesized by a simple procedure of mechanical mixing in a centrifugal mixer. The composites rGO/NIs display a good storage performance, the best being the Se-containing analogue. Full article

(This article belongs to the Special Issue Size-Dependent Effects in Materials for Environmental Protection and Energy Application (2nd Edition))

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14 pages, 10139 KB

Open AccessEditor’s ChoiceArticle

Ultra-Low Core Loss and High-Frequency Permeability Stability in Hot-Press Sintered FeSi Soft Magnetic Composites by Fe₂O₃ Nanoparticles Air Gap Filling

by Muhammad Arif, Donghun Han, Wonchan Shin, Seunghun Cha, Changsun Pak, Youngkwang Kim, Sangwoo Kim, Bowha Lee and Jongsoo Rhyee

Materials 2025, 18(9), 2013; https://doi.org/10.3390/ma18092013 - 29 Apr 2025

Cited by 2 | Viewed by 1850

Abstract

Soft magnetic materials are crucial in motors, generators, transformers, and many electronic devices. We synthesized the FeSi soft magnetic composites (SMCs) with different doping contents of Fe₂O₃ nanopowders as fillers via the hot-press sintering technique. This work explores the incorporation [...] Read more.

Soft magnetic materials are crucial in motors, generators, transformers, and many electronic devices. We synthesized the FeSi soft magnetic composites (SMCs) with different doping contents of Fe₂O₃ nanopowders as fillers via the hot-press sintering technique. This work explores the incorporation of high-resistivity magnetic fillers through a novel compaction technique and investigates the influence of Fe₂O₃ nanopowder on the structure and magnetic properties of Fe₂O₃ nanopowder-filled composites. The finding reveals that Fe₂O₃ nanopowders effectively fill the air gaps between FeSi powders, increasing SMC density. Moreover, all samples exhibit excellent effective permeability frequency stability, ranging from 15 kHz to 100 kHz. Notably, the effective permeability µ_e improves from 22.32 to 30.45, a 36.42% increase, when the Fe₂O₃ doping concentration increases from 0 to 2 wt%. Adding Fe₂O₃ nanopowders also enhances electrical resistivity, leading to a 37.21% reduction in eddy current loss in samples for 5 wt% Fe₂O₃ addition, compared to undoped samples. Furthermore, as Fe₂O₃ content increases from 0 to 5 wt%, the power loss P_cv of the Fe₂O₃-doped Fe-6.5Si SMCs decreases from 25.63 kW/m³ to 16.13 kW/m³, a 37% reduction. These results suggest that Fe₂O₃-doped FeSi SMCs, with their superior soft magnetic properties, hold significant potential for use in high-power and high-frequency electronic applications. Full article

(This article belongs to the Section Materials Chemistry)

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14 pages, 5435 KB

Open AccessEditor’s ChoiceArticle

Electroanalysis of Apocynin Part 2: Investigations on a Boron-Doped Diamond Electrode in Aqueous Buffered Solutions

by Agata Skorupa, Magdalena Jakubczyk and Slawomir Michalkiewicz

Materials 2025, 18(9), 2044; https://doi.org/10.3390/ma18092044 - 29 Apr 2025

Viewed by 534

Abstract

In this study, the voltammetric behavior of apocynin on a boron-doped diamond electrode in a phosphate buffer (pH 7.3) has been reported for the first time. The oxidation process is quasi-reversible, diffusion-controlled, and involves one electron and one proton. The product of the [...] Read more.

In this study, the voltammetric behavior of apocynin on a boron-doped diamond electrode in a phosphate buffer (pH 7.3) has been reported for the first time. The oxidation process is quasi-reversible, diffusion-controlled, and involves one electron and one proton. The product of the electrode reaction is an unstable radical that undergoes successive chemical transformations near the working electrode. The proposed mechanism of this process can be described as E_qC_i and served as the basis for the development of a new voltammetric method for determining apocynin in natural samples. The analytical signal was the anodic peak on DPV curves at a potential of 0.605 V vs. Ag/AgCl. A linear response was observed in the concentration range of 0.213–27.08 mg L⁻¹. The estimated LOD and LOQ values were 0.071 and 0.213 mg L⁻¹, respectively. The effectiveness of the method was demonstrated both in control determinations and in the analysis of the dietary supplement. This procedure is simple, fast, sensitive, selective, and requires no complicated sample preparation, which is limited only to a simple extraction with ethanol. The low consumption of non-toxic reagents makes it environmentally friendly. To the best of our knowledge, this is the first presentation of a voltammetric procedure to determine this analyte studied in a phosphate buffer solution on a boron-doped diamond electrode. It can also be easily adapted to determine other phenolic compounds with antioxidant properties in various matrices. Full article

(This article belongs to the Special Issue Advanced Research of Organic Molecules and Materials for Modern Chemical and Biological Applications)

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18 pages, 5896 KB

Open AccessEditor’s ChoiceArticle

Efficiency of Alternative Reinforcement Methods for Wooden Ceilings and Their Ecological Aspects

by Karl Deix, Christian Huber and Josip Gogic

Materials 2025, 18(9), 2032; https://doi.org/10.3390/ma18092032 - 29 Apr 2025

Viewed by 599

Abstract

In the case of load increases and the refurbishment of existing buildings, it is often necessary to carry out strengthening measures on existing timber beams. When timber concrete composite (TCC) ceilings cannot be used, it is possible to reinforce the undersides of the [...] Read more.

In the case of load increases and the refurbishment of existing buildings, it is often necessary to carry out strengthening measures on existing timber beams. When timber concrete composite (TCC) ceilings cannot be used, it is possible to reinforce the undersides of the beams with structural steel or fiber composites (aramid or carbon-fiber-reinforced polymer). This work investigates how significant effects on the load-bearing and deformation behavior can be achieved with these materials in terms of construction practice. The article is intended to show structural engineers which reinforcement measures lead to which forces, deformations, etc., and how these are utilized. This should form the basis for the planning of reinforcement measures, as it is not clear from the beginning whether AFRP, CFRP, or steel is the most suitable material. For this purpose, a comparative parameter study was carried out under practical conditions and with a variable degree of reinforcement using the corresponding formulas. The internal forces in the timber and reinforcement cross-sections, the deflection behavior, and the failure loads at the strength and design levels were calculated. It was demonstrated that, particularly for steel and carbon-fiber-reinforced polymer (CFRP) reinforcements, significant increases in the ultimate load can be achieved and the often-important deformation behavior can be significantly improved. Especially the steel variant leads to high improvements in deflection and breaking load behavior, with the base material (wood) also being utilized more economically as a result. A comparative ecological study in the form of the global warming potential showed that reinforcement methods are also advantageous from the point of view of sustainability compared to renovations with timber concrete composite slabs or new concrete slabs. Full article

(This article belongs to the Section Advanced Composites)

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16 pages, 8149 KB

Open AccessEditor’s ChoiceArticle

Multifunctional Sol–Gel Coatings for Both Anticorrosion and Electrical Conduction Properties

by Clément Genet, Hiba Azougaghe, Edouard Bréniaux, Robin Montpellaz, Marie Gressier, Florence Ansart, Olivier Gavard and Marie-Joëlle Menu

Materials 2025, 18(9), 2011; https://doi.org/10.3390/ma18092011 - 29 Apr 2025

Viewed by 687

Abstract

This work is part of a current and essential issue aiming to find a solution for the replacement of chromium(VI) and cadmium in the surface treatment process applied to electrical connectors. The application of a protective coating obtained by the sol–gel route proves [...] Read more.

This work is part of a current and essential issue aiming to find a solution for the replacement of chromium(VI) and cadmium in the surface treatment process applied to electrical connectors. The application of a protective coating obtained by the sol–gel route proves to be an interesting alternative method and numerous studies describe efficient anticorrosion coatings to protect various metallic alloys. The issue of electrical connectors made of 6061 alloy is to combine anticorrosion protection and electrical conduction, which are antagonistic properties, so multifunctional sol–gel coatings and/or architectures have to be synthesized and shaped on connectors. In this work, several experimental parameters, such as the type of carbon filler, the hydrolysis ratio, the precursors’ introduction order are studied and evaluated to achieve industrial requirements. Thus, aqueous suspensions of carbon fillers have been introduced into sol–gel formulations to give rise to conductive coatings (200–500 mΩ_□) with high anticorrosion properties (500 h NSS resistance), in which thickness is less than 10 microns. The incorporation of organic additives poly(2-ethyl-2-oxazoline) or hydroxypropylmethylcellulose positively impacts the flash point of the sol (>60 °C) making the sol–gel process compatible with the HSE recommendation and the ATEX standard. Full article

(This article belongs to the Section Materials Chemistry)

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35 pages, 5269 KB

Open AccessEditor’s ChoiceArticle

The Quantum Transport of Dirac Fermions in Selected Graphene Nanosystems Away from the Charge Neutrality Point

by Adam Rycerz

Materials 2025, 18(9), 2036; https://doi.org/10.3390/ma18092036 - 29 Apr 2025

Viewed by 1046

Abstract

The peculiar electronic properties of graphene, including the universal dc conductivity and the pseudodiffusive shot noise, are usually found in a small vicinity close to the charge neutrality point, away from which the electron’s effective mass raises, and nanostructures in graphene start to [...] Read more.

The peculiar electronic properties of graphene, including the universal dc conductivity and the pseudodiffusive shot noise, are usually found in a small vicinity close to the charge neutrality point, away from which the electron’s effective mass raises, and nanostructures in graphene start to behave similarly to familiar Sharvin contacts in semiconducting heterostructures. Recently, it was pointed out that as long as abrupt potential steps separate the sample area from the leads, some graphene-specific features can be identified relatively far from the charge neutrality point. These features include greater conductance reduction and shot noise enhancement compared to the standard Sharvin values. The purpose of this paper is twofold: First, we extend the previous analysis based on the effective Dirac equation, and derive the formulas that allow the calculation of the arbitrary charge transfer cumulant for doped graphene. Second, the results of the analytic considerations are compared with numerical simulations of quantum transport on the honeycomb lattice for selected nanosystems for which considerations starting from the Dirac equation cannot be directly adapted. For a wedge-shaped constriction with zigzag edges, the transport characteristics can be tuned from graphene-specific (sub-Sharvin) values to standard Sharvin values by varying the electrostatic potential profile in the narrowest section. A similar scenario is followed by the half-Corbino disk. In contrast, a circular quantum dot with two narrow openings showing a mixed behavior appears: the conductance is close to the Sharvin value, while the Fano factor approaches the value characterizing the symmetric chaotic cavity. Carving a hole in the quantum dot to eliminate direct trajectories between the openings reduces the conductance to sub-Sharvin value, but the Fano factor is unaffected. Our results suggest that experimental attempts to verify the predictions for the sub-Sharvin transport regime should focus on systems with relatively wide openings, where the scattering at the sample edges is insignificant next to the scattering at the sample–lead interfaces. Full article

(This article belongs to the Special Issue Quantum Transport in Novel 2D Materials and Structures)

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26 pages, 4573 KB

Open AccessEditor’s ChoiceReview

Flexible Glass: Myth and Photonic Technology

by Giancarlo C. Righini, Maurizio Ferrari, Anna Lukowiak and Guglielmo Macrelli

Materials 2025, 18(9), 2010; https://doi.org/10.3390/ma18092010 - 29 Apr 2025

Viewed by 3307

Abstract

The recent fast advances in consumer electronics, especially in cell phones and displays, have led to the development of ultra-thin, hence flexible, glasses. Once available, such flexible glasses have proven to be of great interest and usefulness in other fields, too. Flexible photonics, [...] Read more.

The recent fast advances in consumer electronics, especially in cell phones and displays, have led to the development of ultra-thin, hence flexible, glasses. Once available, such flexible glasses have proven to be of great interest and usefulness in other fields, too. Flexible photonics, for instance, has quickly taken advantage of this new material. At first sight, “flexible glass” appears to be an oxymoron. Glass is, by definition, fragile and highly breakable; its structure has puzzled scientists for decades, but it is evident that in most conditions it is a rigid material, so how can it bend? This possibility, however, has aroused the interest of artists and craftsmen since ancient times; thus, in Roman times the myth of flexible glass was born. Furthermore, the myth appeared again in the Middle Age, connected to a religious miracle. Today, however, flexible glass is no more a myth but a reality due to the fact that current technology permits us to produce micron-thick glass sheets, and any ultra-thin material can be bent. Flexibility is coming from the present capability to manufacture glass sheets at a tens of microns thickness coupled with the development of strengthening methods; it is also worth highlighting that, on the micrometric and nanometric scales, silicate glass presents plastic behavior. The most significant application area of flexible glass is consumer electronics, for the displays of smartphones and tablets, and for wearables, where flexibility and durability are crucial. Automotive and medical sectors are also gaining importance. A very relevant field, both for the market and the technological progress, is solar photovoltaics; mechanical flexibility and lightweight have allowed solar cells to evolve toward devices that possess the advantages of conformability, bendability, wearability, and moldability. The mature roll-to-roll manufacturing technology also allows for high-performance devices at a low cost. Here, a brief overview of the history of flexible glass and some examples of its application in solar photovoltaics are presented. Full article

(This article belongs to the Special Issue Advances in Electronic and Photonic Materials)

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14 pages, 6228 KB

Open AccessEditor’s ChoiceArticle

Microstructure and Mechanical Property of 6082 Aluminum Alloy via Sc and Zr Addition Combined with Squeeze Casting

by Yushi Qi, Fangming Wei, Yu Wang, Yu Jin, Xusheng Chang and Gang Chen

Materials 2025, 18(9), 1988; https://doi.org/10.3390/ma18091988 - 27 Apr 2025

Cited by 1 | Viewed by 1253

Abstract

To enhance the mechanical properties of 6082 aluminum alloy, a novel Sc- and Zr-microalloyed 6082 alloy was fabricated through squeeze casting technology. Microalloying with Sc and Zr substantially refined the microstructure of alloy, achieving an average grain size of 136.36 μm—a 31.7% reduction [...] Read more.

To enhance the mechanical properties of 6082 aluminum alloy, a novel Sc- and Zr-microalloyed 6082 alloy was fabricated through squeeze casting technology. Microalloying with Sc and Zr substantially refined the microstructure of alloy, achieving an average grain size of 136.36 μm—a 31.7% reduction compared to the baseline 6082 alloy. Furthermore, the addition of Sc and Zr effectively refined the coarse AlFeMnSi intermetallic phases, mitigating their inherent brittleness. The Sc/Zr-modified alloy exhibited delayed age-hardening kinetics, requiring 100% longer aging time to reach peak hardness due to Sc/Zr-induced retardation of β’’-phase precipitation. The optimized alloy demonstrated better mechanical properties, showing 10.4%, 8.0%, and 71.8% enhancements in yield strength, ultimate tensile strength, and elongation, respectively, over the non-microalloyed counterpart. The squeeze-cast Sc/Zr-modified alloy valve body showed yield strength exceeding 300 MPa and elongation above 10% across various sections, which verifies the effectiveness of this integrated microalloying and forming approach. Full article

(This article belongs to the Special Issue Review and Feature Papers in "Metals and Alloys" Section (2nd Edition))

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25 pages, 16068 KB

Open AccessEditor’s ChoiceArticle

Mechanical Properties and Fracture Analysis of Advanced Nickel-Based Nanomembranes

by Janik Marius Lück and Joachim Rösler

Materials 2025, 18(9), 1961; https://doi.org/10.3390/ma18091961 - 25 Apr 2025

Cited by 2 | Viewed by 468

Abstract

Nanoporous membranes based on the single crystalline nickel-based superalloy CMSX-4 are a promising class of materials for membranes, especially for use in premix membrane emulsification. In addition to the pore size, the strength and stability of the membrane structure are key factors for [...] Read more.

Nanoporous membranes based on the single crystalline nickel-based superalloy CMSX-4 are a promising class of materials for membranes, especially for use in premix membrane emulsification. In addition to the pore size, the strength and stability of the membrane structure are key factors for subsequent use. The production of the membranes is based on the directional coarsening of the γ/γ′-microstructure by creep deformation, in which the material is subjected to a tensile load at high temperatures so that a bicontinuous network of the γ- and γ′-phase is formed. The subsequent dissolution of the γ-phase leaves a network of γ′-phase, which can be used as a membrane structure; the former γ-matrix channels now serve as pores. Previous investigations focusing on the evolution of the microstructure during membrane fabrication found that a particularly small pore size can be achieved when the creep deformation temperature is lowered from 1000 °C to 950 °C while increasing the stress from 170 MPa to 250 MPa. This study will now investigate the strength and fracture behaviour of membranes produced by these improved parameters. For this purpose, four creep states with creep strains between 1.3% and 5.7% are investigated in tensile tests at room temperature, with the load being applied perpendicular and parallel to the raft structure. The results show that the strength of nanomembranes during perpendicular loading essentially depends on the cross-linking between γ′-rafts. Generally, an increase in creep strain leads to an increase of the cross-linking resulting in higher tensile strength. During parallel loading, γ′-inhomogeneities play an important role resulting in a loss of strength. The analysis of the fracture surfaces and evaluation of EBSD measurements reveal an insufficient cross-linking between dendrites and around γ′-inhomogeneities, leading to preferred crack paths. Therefore, the differences in orientation within the single crystal play a key role in the strength of the nanomembranes. Full article

(This article belongs to the Special Issue Advanced Nanoporous and Mesoporous Materials)

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26 pages, 5352 KB

Open AccessEditor’s ChoiceArticle

Optimization of Rotary Friction Welding Parameters Through AI-Augmented Digital Twin Systems

by Piotr Lacki, Janina Adamus, Kuba Lachs and Wiktor Lacki

Materials 2025, 18(9), 1923; https://doi.org/10.3390/ma18091923 - 24 Apr 2025

Cited by 1 | Viewed by 1087

Abstract

In this study, Artificial Neural Networks (ANN) were employed to develop a Digital Twin (DT) of the Rotary Friction Welding (RFW) process. The neural network models were trained to predict the peak temperature generated during the welding process of dissimilar Ti Grade 2/AA [...] Read more.

In this study, Artificial Neural Networks (ANN) were employed to develop a Digital Twin (DT) of the Rotary Friction Welding (RFW) process. The neural network models were trained to predict the peak temperature generated during the welding process of dissimilar Ti Grade 2/AA 5005 joints over a temperature range of 20–640 °C. This prediction was based on a parametric numerical model of the RFW process constructed using the Finite Element Method (FEM) within the ADINA System software. Numerical simulations enabled a detailed analysis of the temperature distribution within the weldment. Accurate temperature predictions are essential for assessing the mechanical properties and microstructural integrity of the welded materials. Artificial Intelligence (AI) models, trained on historical data and real-time inputs, dynamically adjust critical process parameters—such as rotational speed, axial force, and friction time—to maintain optimal weld quality. A key advantage of employing AI-augmented DT systems in the RFW process is the ability to conduct real-time (less than 0.1 s) optimization and adaptive control. By integrating a Genetic Algorithm (GA) with the DT algorithm of the RFW process, the authors developed an effective tool for analyzing parameters such as axial force and rotational speed, in order to determine the optimal welding conditions, which translates into improved joint quality, minimized defects, and maximized process efficiency. Full article

(This article belongs to the Special Issue Artificial Intelligence in Materials Science and Engineering)

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12 pages, 2913 KB

Open AccessEditor’s ChoiceArticle

Structural and Magnetic Characterization of Mechanically Alloyed (Fe₂O₃)_1−x(Al₂O₃)_x Solid Solutions via Pulsed Neutron Powder Diffraction

by Dong Luo, Hayato Nakaishi, Takeshi Yabutsuka, Takashi Saito, Takashi Kamiyama, Masato Hagihala and Shigeomi Takai

Materials 2025, 18(9), 1911; https://doi.org/10.3390/ma18091911 - 23 Apr 2025

Cited by 1 | Viewed by 959

Abstract

Neutron powder diffraction experiments were carried out to characterize mechanochemically synthesized (Fe₂O₃)_1−x(Al₂O₃)_x solid solutions with corundum-type structure, focusing on their lattice and magnetic structures with varying temperature and composition. The neutron diffraction [...] Read more.

Neutron powder diffraction experiments were carried out to characterize mechanochemically synthesized (Fe₂O₃)_1−x(Al₂O₃)_x solid solutions with corundum-type structure, focusing on their lattice and magnetic structures with varying temperature and composition. The neutron diffraction experiments for (Fe₂O₃)_0.5(Al₂O₃)_0.5 in the temperature range between 4 K and 300 K reveal that no significant structural phase transition occurred. The behavior of temperature variation of lattice parameters is different from α-Fe₂O₃ and α-Al₂O₃ and reveals the thermal expansion coefficients of α_a = 5.76(2) × 10⁻⁶ K⁻¹ and α_c = 6.19(5) × 10⁻⁶ K⁻¹ between 200 K and 300 K. The room temperature neutron diffraction of (Fe₂O₃)_1−x(Al₂O₃)_x shows a linear decrease in lattice parameters with the aluminum substitution, following Vegard’s law, along with a decrease in the magnetic moment, indicating the dilution effect on spin interactions. With the increase in the aluminum substitution from x = 0 to 0.5, the deduced magnetic moment decreases from 2.224 μ_B to 0.862 μ_B. Full article

(This article belongs to the Section Materials Chemistry)

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23 pages, 3710 KB

Open AccessEditor’s ChoiceArticle

Investigation and Optimization of Process Parameters on Growth Rate in Al₂O₃ Atomic Layer Deposition (ALD) Using Statistical Approach

by Dongqing Pan and Yu Lei

Materials 2025, 18(9), 1918; https://doi.org/10.3390/ma18091918 - 23 Apr 2025

Cited by 1 | Viewed by 1087

Abstract

The improvement in ALD growth rate has always been challenging due to its slow atomic-scale depositions. Although Al₂O₃ ALD is one of the most widely used ALD processes, the effects of its process parameters on growth rate have not been [...] Read more.

The improvement in ALD growth rate has always been challenging due to its slow atomic-scale depositions. Although Al₂O₃ ALD is one of the most widely used ALD processes, the effects of its process parameters on growth rate have not been systematically analyzed using statistical approaches. These statistical methods offer better efficiency and effectiveness compared to traditional techniques for studying complex processes like ALD. This paper presents a systematic investigation and optimization of four process parameters on growth rate of Al₂O₃ ALD thin films using a full factorial design of experiments (DOE) approach. Statistical analysis revealed that deposition temperature is the only statistically significant factor in Al₂O₃ ALD process, while argon gas flow rate, pulsing time and purging time are tested nonsignificant. Significant interactions were found between deposition temperature and purging time, and between pulsing time and purging time, with all other interactions being nonsignificant. Optimal process settings for higher deposition rate were identified: the temperature and gas flow rate are set at lower levels, while pulsing time and purging time are set at higher levels. Full article

(This article belongs to the Special Issue Materials Innovation Through Atomic Layer Deposition: Process Optimization, Material Properties, and Applications)

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30 pages, 3765 KB

Open AccessEditor’s ChoiceArticle

Antibacterial Activity of GO-Based Composites Enhanced by Phosphonate-Functionalized Ionic Liquids and Silver

by Xinyu Liu, Xing Zhao, Hongda Qiu, Weida Liang, Linlin Liu, Yunyu Sun, Lingling Zhao, Xiao Wang and Hongze Liang

Materials 2025, 18(8), 1889; https://doi.org/10.3390/ma18081889 - 21 Apr 2025

Viewed by 1171

Abstract

The development of antibiotic-independent antimicrobial materials is critical for addressing bacterial resistance to conventional antibiotics. Currently, there is a lack of comprehensive understanding of ionic liquid-modified composites in antimicrobial applications. Here, we innovatively prepared GO-based composites modified with phosphonate ionic liquids via a [...] Read more.

The development of antibiotic-independent antimicrobial materials is critical for addressing bacterial resistance to conventional antibiotics. Currently, there is a lack of comprehensive understanding of ionic liquid-modified composites in antimicrobial applications. Here, we innovatively prepared GO-based composites modified with phosphonate ionic liquids via a series of surface functionalizations. The resulting antibacterial composites exhibit significant broad-spectrum activity against both Gram-negative and Gram-positive bacteria, including drug-resistant strains, with stronger efficacy against Gram-negative species. Additionally, the material features excellent long-term reusability and the ability to inhibit/destroy biofilms, which is vital for combating persistent infections. Mechanistic studies reveal its antibacterial effects through multiple pathways: disrupting bacterial membranes, inducing ROS, and inactivating intracellular substances—mechanisms less likely to promote resistance. Overall, these phosphonate ionic liquid-modified polycationic materials demonstrate substantial potential in treating bacterial infections, offering a promising strategy to tackle antibiotic resistance challenges. Full article

(This article belongs to the Special Issue Ionic Liquids: New Trends in Advanced Applications)

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13 pages, 4511 KB

Open AccessEditor’s ChoiceArticle

Crystallographic Engineering of CrN Buffer Layers for GaN Thin Film Epitaxy

by Kyu-Yeon Shim, Seongho Kang, Min-Joo Ahn, Yukyeong Cha, Eojin-Gyere Ham, Dohoon Kim and Dongjin Byun

Materials 2025, 18(8), 1817; https://doi.org/10.3390/ma18081817 - 16 Apr 2025

Cited by 1 | Viewed by 837

Abstract

Gallium nitride (GaN) is commonly used in various semiconductor systems owing to its high mobility and thermal stability; however, the production of GaN thin films using the currently employed methods requires improvement. To facilitate the growth of high-quality GaN epitaxial thin films, this [...] Read more.

Gallium nitride (GaN) is commonly used in various semiconductor systems owing to its high mobility and thermal stability; however, the production of GaN thin films using the currently employed methods requires improvement. To facilitate the growth of high-quality GaN epitaxial thin films, this study explored the crystallographic structures, properties, and influences of chromium nitride (CrN) buffer layers sputtered under various conditions. The crystallographic orientation of CrN played a crucial role in determining the GaN film quality. For example, even when the crystallinity of the CrN (111) plane was relatively low, a single-phase CrN (111) buffer layer could provide a more favorable template for GaN epitaxy compared to cases where both the CrN (111) and Cr₂N (110) phases coexisted. The significance of a low-temperature (LT) GaN nucleation layer deposited onto the CrN buffer layers was assessed using atomic force microscopy and contact angle measurements. The X-ray phi scan results confirmed the six-fold symmetry of the grown GaN, further emphasizing the contribution of an LT-GaN nucleation layer. These findings offer insights into the underlying mechanisms governing GaN thin film growth and provide guidance for the optimization of the buffer layer conditions to achieve high-quality GaN epitaxial films. Full article

(This article belongs to the Section Thin Films and Interfaces)

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47 pages, 4349 KB

Open AccessEditor’s ChoiceReview

Metal Nanocomposites as Biosensors for Biological Fluids Analysis

by Dan Chicea and Alexandra Nicolae-Maranciuc

Materials 2025, 18(8), 1809; https://doi.org/10.3390/ma18081809 - 15 Apr 2025

Cited by 2 | Viewed by 1263

Abstract

Metal nanocomposites are rapidly emerging as a powerful platform for biosensing applications, particularly in the analysis of biological fluids. This review paper examines the recent advancements in the development and application of metal nanocomposites as biosensors for detecting various analytes in complex biological [...] Read more.

Metal nanocomposites are rapidly emerging as a powerful platform for biosensing applications, particularly in the analysis of biological fluids. This review paper examines the recent advancements in the development and application of metal nanocomposites as biosensors for detecting various analytes in complex biological matrices such as blood, serum, urine, and saliva. We discuss the unique physicochemical properties of metal nanocomposites, including their high surface area, enhanced conductivity, and tunable optical and electrochemical characteristics, which contribute to their superior sensing capabilities. The review will cover various fabrication techniques, focusing on their impact on the sensitivity, selectivity, and stability of the resulting biosensors. Furthermore, we will analyze the diverse applications of these biosensors in the detection of disease biomarkers, environmental toxins, and therapeutic drugs within biological fluids. Finally, we will address the current challenges and future perspectives of this field, highlighting the potential for improved diagnostic tools and personalized medicine through the continued development of advanced metal nanocomposite-based biosensors. Full article

(This article belongs to the Special Issue Progress and Challenges of Advanced Metallic Materials and Composites)

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15 pages, 3554 KB

Open AccessEditor’s ChoiceArticle

Study of ZrO₂ Gate Dielectric with Thin SiO₂ Interfacial Layer in 4H-SiC Trench MOS Capacitors

by Qimin Huang, Yunduo Guo, Anfeng Wang, Zhaopeng Bai, Lin Gu, Zhenyu Wang, Chengxi Ding, Yi Shen, Hongping Ma and Qingchun Zhang

Materials 2025, 18(8), 1741; https://doi.org/10.3390/ma18081741 - 10 Apr 2025

Cited by 2 | Viewed by 1188

Abstract

The transition of SiC MOSFET structure from planar to trench-based architectures requires the optimization of gate dielectric layers to improve device performance. This study utilizes a range of characterization techniques to explore the interfacial properties of ZrO₂ and SiO₂/ZrO₂ [...] Read more.

The transition of SiC MOSFET structure from planar to trench-based architectures requires the optimization of gate dielectric layers to improve device performance. This study utilizes a range of characterization techniques to explore the interfacial properties of ZrO₂ and SiO₂/ZrO₂ gate dielectric films, grown via atomic layer deposition (ALD) in SiC epitaxial trench structures to assess their performance and suitability for device applications. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) measurements showed the deposition of smooth film morphologies with roughness below 1 nm for both ZrO₂ and SiO₂/ZrO₂ gate dielectrics, while SE measurements revealed comparable physical thicknesses of 40.73 nm for ZrO₂ and 41.55 nm for SiO₂/ZrO₂. X-ray photoelectron spectroscopy (XPS) shows that in SiO₂/ZrO₂ thin films, the binding energies of Zr 3d_5/2 and Zr 3d_3/2 peaks shift upward compared to pure ZrO₂. Electrical characterization showed an enhancement of E_BR (3.76 to 5.78 MV·cm⁻¹) and a decrease of I_{ON_EBR} (1.94 to 2.09 × 10⁻³ A·cm⁻²) for the SiO₂/ZrO₂ stacks. Conduction mechanism analysis identified suppressed Schottky emission in the stacked film. This indicates that the incorporation of a thin SiO₂ layer effectively mitigates the small bandgap offset, enhances the breakdown electric field, reduces leakage current, and improves device performance. Full article

(This article belongs to the Special Issue Feature Papers in Materials Physics (2nd Edition))

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14 pages, 8353 KB

Open AccessEditor’s ChoiceArticle

Design and Characterization of an Equibiaxial Multi-Electrode Dielectric Elastomer Actuator

by Simon Holzer, Bhawnath Tiwari, Stefania Konstantinidi, Yoan Civet and Yves Perriard

Materials 2025, 18(8), 1693; https://doi.org/10.3390/ma18081693 - 8 Apr 2025

Viewed by 672

Abstract

With the ongoing journey of automation advancements and a trend towards miniaturization, the choice of actuator plays a crucial role. Over recent years, soft actuators have demonstrated their usefulness in various applications, especially where light weight and high strain are required. Dielectric elastomer [...] Read more.

With the ongoing journey of automation advancements and a trend towards miniaturization, the choice of actuator plays a crucial role. Over recent years, soft actuators have demonstrated their usefulness in various applications, especially where light weight and high strain are required. Dielectric elastomer actuators (DEAs) are a class of soft actuators that provide high-strain actuation possibilities in applications like biomedicine, logistics, or consumer electronics. A variety of work featuring DEAs for actuation has been carried out in recent years, but a single work detailing the design conception, fabrication, modeling and experimental validation is lacking, especially in the context of achieving high strains with the integration of multiple electrodes and their interaction. This work discusses these issues with an equibiaxial DEA, enabling optimized equibiaxial strain patterns due to full use of the available actuation area. The developed DEA can achieve an equibiaxial strain of 12.75% for actuation at 60 V μm⁻¹ over an active area of 7 cm² which is an improvement of 1.3 times compared to traditional dot actuators. These properties position the device as a promising alternative for various applications like cell cultures or microassembly and provide an advantage of optimized use of passive regions within the actuator. Full article

(This article belongs to the Special Issue Electroactive Polymers: Fundamentals and Applications)

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30 pages, 4998 KB

Open AccessEditor’s ChoiceArticle

A Material Study of Persian-Period Silver Coins and Hacksilber from Samaria

by Dana Ashkenazi, Maayan Cohen, Haim Gitler, Mati Johananoff and Oren Tal

Materials 2025, 18(7), 1678; https://doi.org/10.3390/ma18071678 - 7 Apr 2025

Viewed by 1259

Abstract

An assembly of fourth-century BCE Samarian silver coins and late-fifth-century BCE Samarian cut silver sheets, Sidonian and Philistian coins from a hacksilber hoard allegedly found in the region of Samaria belonging to the David and Jemima Jeselsohn collection, were characterized by metallurgical analyses. [...] Read more.

An assembly of fourth-century BCE Samarian silver coins and late-fifth-century BCE Samarian cut silver sheets, Sidonian and Philistian coins from a hacksilber hoard allegedly found in the region of Samaria belonging to the David and Jemima Jeselsohn collection, were characterized by metallurgical analyses. The aims of the research were to identify the items’ composition and manufacturing processes. We affirmed that the Samarian coins were made of silver–copper alloy produced by a controlled process. The microstructural and elemental analyses revealed that the sheets were produced from various materials, including pure silver, silver–copper, and silver–copper–gold alloys, whereas the Sidonian and Philistian coins were made of silver–copper alloy. Continuity in style and production techniques was observed. This information provides a better understanding of the material culture and technological skills in the Persian-period province of Samaria. Full article

(This article belongs to the Section Metals and Alloys)

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31 pages, 5436 KB

Open AccessEditor’s ChoiceArticle

Study of the Relationship Between the Structures and Biological Activity of Herbicides Derived from Phenoxyacetic Acid

by Grzegorz Świderski, Natalia Kowalczyk, Gabriela Tyniecka, Monika Kalinowska, Renata Łyszczek, Aleksandra Bocian, Ewa Ciszkowicz, Leszek Siergiejczyk, Małgorzata Pawłowska and Jacek Czerwiński

Materials 2025, 18(7), 1680; https://doi.org/10.3390/ma18071680 - 7 Apr 2025

Cited by 1 | Viewed by 2002

Abstract

Chloroderivatives of phenoxyacetic acid are a group of compounds commonly used as plant protection products. Differences in the molecular structure of these compounds are related to varying substitution and the number of chlorine atoms in the aromatic ring. Different molecular structures may affect [...] Read more.

Chloroderivatives of phenoxyacetic acid are a group of compounds commonly used as plant protection products. Differences in the molecular structure of these compounds are related to varying substitution and the number of chlorine atoms in the aromatic ring. Different molecular structures may affect the activity of these compounds, their physicochemical properties, as well as their toxicity and biological effects. A group of 6 chemical compounds derived from phenoxyacetic acid was tested. The molecular structure was analysed using spectroscopic methods (FTIR, FTRaman, UV-VIS, ¹HNMR, ¹³CNMR) and quantum chemical computational methods (DFT). The reactivity of the tested compounds was determined using DFT calculations and experimentally in reaction with a hydroxyl radical. The electronic charge distribution of NBO, CHelpG and ESP was analysed and aromaticity indices were calculated for theoretically modeled structures and structures examined by X-ray diffraction (data obtained from the CSD database). Phenoxyacetic acid derivatives were tested for antimicrobial activity on soil bacterial strains. Cytotoxicity tests were performed on normal human skin fibroblasts (BJ CRL-2522) and the human prostate cancer cell line (DU-145 HTB-81). The purpose of this study was to investigate the relationship between the molecular structure of phenoxyacetic acid derivatives and their reactivity and biological activity. Full article

(This article belongs to the Special Issue From Molecular to Supramolecular Materials)

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19 pages, 5369 KB

Open AccessEditor’s ChoiceArticle

Interactions of Terahertz Photons with Phonons of Two-Dimensional van der Waals MoS₂/WSe₂/MoS₂ Heterostructures and Thermal Responses

by Jingwen Huang, Ningsheng Xu, Yumao Wu, Xue Ran, Yue Fang, Hongjia Zhu, Weiliang Wang, Huanjun Chen and Shaozhi Deng

Materials 2025, 18(7), 1665; https://doi.org/10.3390/ma18071665 - 4 Apr 2025

Cited by 1 | Viewed by 1575

Abstract

The interaction between terahertz (THz) photons and phonons of materials is crucial for the development of THz photonics. In this work, typical two-dimensional (2D) van der Waals (vdW) transition metal chalcogenide (TMD) layers and heterostructures are used in THz time-domain spectroscopy (TDS) measurements, [...] Read more.

The interaction between terahertz (THz) photons and phonons of materials is crucial for the development of THz photonics. In this work, typical two-dimensional (2D) van der Waals (vdW) transition metal chalcogenide (TMD) layers and heterostructures are used in THz time-domain spectroscopy (TDS) measurements, low-wavenumber Raman spectroscopy measurements, calculation of 2D materials’ phonon spectra, and theoretical analysis of thermal responses. The TDS results reveal strong absorption of THz photons in the frequency range of 2.5–10 THz. The low-wavenumber Raman spectra show the phonon vibration characteristics and are used to establish phonon energy bands. We also set up a computational simulation model for thermal responses. The temperature increases and distributions in the individual layers and their heterostructures are calculated, showing that THz photon absorption results in significant increases in temperature and differences in the heterostructures. These give rise to interesting photothermal effects, including the Seebeck effect, resulting in voltages across the heterostructures. These findings provide valuable guidance for the potential optoelectronic application of the 2D vdW heterostructures. Full article

(This article belongs to the Special Issue Terahertz Vibrational Spectroscopy in Advanced Materials)

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21 pages, 3015 KB

Open AccessEditor’s ChoiceArticle

Monitoring Antioxidant Consumption and Build-Up in Polypropylene During Open-Loop and Closed-Loop Mechanical Recycling

by Niek Knoben, Max Vanhouttem, Aike Wypkema and Nithya Subramanian

Materials 2025, 18(7), 1640; https://doi.org/10.3390/ma18071640 - 3 Apr 2025

Viewed by 2270

Abstract

Polypropylene (PP), a widely used recyclable plastic in packaging and engineering applications, is prone to thermo-oxidative degradation during reprocessing and molding at high temperatures. Antioxidants (AOs) are essential for stabilizing PP in both its virgin and recycled states. The quantity of AO added [...] Read more.

Polypropylene (PP), a widely used recyclable plastic in packaging and engineering applications, is prone to thermo-oxidative degradation during reprocessing and molding at high temperatures. Antioxidants (AOs) are essential for stabilizing PP in both its virgin and recycled states. The quantity of AO added is critical: insufficient amounts can lead to poor stabilization, while excessive amounts can cause safety concerns due to build-up. This study presents a modified approach to measure the Oxidation Induction Temperature (OIT) using Differential Scanning Calorimetry (DSC), particularly for recycled PP from waste that contains unpredictable contaminations. This modified approach ensures the safety of the calorimetry cell by limiting the oxidation reaction and preventing the release of volatile compounds during measurements. By performing DSC measurements in inert environments, we obtain the OIT, which can be correlated to residual intact AO levels. This approach to monitoring AO levels is demonstrated in both open- and closed-loop recycling of rigid PP. Although the presence of contamination is known to catalyze thermo-oxidative degradation in PP, our results indicate that recycled PP from open-loop collection still contains sufficient residual AO that allows it to withstand limited thermal reprocessing. However, this tendency of AO retention leads to significant build-up during closed-loop recycling when AOs are added to each cycle, where the PP grade remains fairly homogeneous and the dispersity (Đ) does not significantly increase over multiple recycling loops. Full article

(This article belongs to the Special Issue Recycling and Degradation of Polymeric Materials: Exploring Different Perspectives in Plastic Waste Management)

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17 pages, 3636 KB

Open AccessEditor’s ChoiceArticle

DFT Investigation of a Direct Z-Scheme Photocatalyst for Overall Water Splitting: Janus Ga₂SSe/Bi₂O₃ Van Der Waals Heterojunction

by Fan Yang, Pascal Boulet and Marie-Christine Record

Materials 2025, 18(7), 1648; https://doi.org/10.3390/ma18071648 - 3 Apr 2025

Cited by 4 | Viewed by 1231

Abstract

Constructing van der Waals heterojunctions with excellent properties has attracted considerable attention in the field of photocatalytic water splitting. In this study, four patterns, coined A, B, C, and D of Janus Ga₂SSe/Bi₂O₃ van der Waals (vdW) heterojunctions [...] Read more.

Constructing van der Waals heterojunctions with excellent properties has attracted considerable attention in the field of photocatalytic water splitting. In this study, four patterns, coined A, B, C, and D of Janus Ga₂SSe/Bi₂O₃ van der Waals (vdW) heterojunctions with different stacking modes, were investigated using first-principles calculations. Their stability, electronic structure, and optical properties were analyzed in detail. Among these, patterns A and C heterojunctions demonstrate stable behavior and operate as direct Z-scheme photocatalysts, exhibiting band gaps of 1.83 eV and 1.62 eV. In addition, the suitable band edge positions make them effective for photocatalytic water decomposition. The built-in electric field across the heterojunction interface effectively inhibits electron-hole recombination, thereby improving the photocatalytic efficiency. The optical absorption coefficients show that patterns A and C heterojunctions exhibit higher light absorption intensity than Ga₂SSe and Bi₂O₃ monolayers, spanning from the ultraviolet to visible range. Their corrected solar-to-hydrogen (STH) efficiencies are 13.60% and 12.08%, respectively. The application of hydrostatic pressure and biaxial tensile strain demonstrate distinct effects on photocatalytic performance: hydrostatic pressure preferentially enhances the hydrogen evolution reaction (HER), while biaxial tensile strain primarily improves the oxygen evolution reaction (OER). Furthermore, the heterojunctions exhibited enhanced optical absorption across the UV-visible spectrum with increasing hydrostatic pressure. Notably, a 1% tensile strain results in an improvement in visible light absorption efficiency. These results demonstrate that Ga₂SSe/Bi₂O₃ heterojunctions hold great promise as direct Z-scheme photocatalysts for overall water splitting. Full article

(This article belongs to the Special Issue Hierarchically Structured Materials for Photocatalysis, Electrocatalysis and Photoelectrocatalysis)

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15 pages, 6248 KB

Open AccessEditor’s ChoiceArticle

Precursor-Derived Mo₂C/SiC Composites with a Two-Dimensional Sheet Structure for Electromagnetic Wave Absorption

by Yang Li, Wen Yang, Jipeng Zhang, Yongzhao Hou, Guangwu Wen, Guodong Xin, Meixian Jiang and Yongqiang Ma

Materials 2025, 18(7), 1573; https://doi.org/10.3390/ma18071573 - 31 Mar 2025

Viewed by 670

Abstract

Precursor-derived silicon carbide (SiC) ceramics have been widely used as absorbing materials, but the residual carbon sink produced by ceramicization limits their application under high-temperature and oxygen-containing conditions, such as the nozzle or jet vane of high-speed aircraft. In this paper, a novel [...] Read more.

Precursor-derived silicon carbide (SiC) ceramics have been widely used as absorbing materials, but the residual carbon sink produced by ceramicization limits their application under high-temperature and oxygen-containing conditions, such as the nozzle or jet vane of high-speed aircraft. In this paper, a novel molybdenum carbide/silicon carbide (Mo₂C/SiC) microwave-absorbing ceramic with a two-dimensional sheet structure was obtained through the pyrolysis of polycarbosilane-coated molybdenum sulfide (PCS@MoS₂). The results indicate that addition of an appropriate amount of MoS₂ can react with the free carbon generated during the pyrolysis of PCS, thereby reducing the material’s carbon content and forming Mo₂C. Concurrently, the layered structural characteristics of MoS₂ are utilized to create a two-dimensional composite structure within the material, which enhances the material’s absorption vastly. The as-prepared Mo₂C/SiC ceramics sintered at 1300 °C exhibit a minimum reflection loss (RL_min) of −46.49 dB at 8.96 GHz with a thickness of 2.6 mm. Additionally, the effective absorption bandwidth (EAB) of Mo₂C/SiC spans the entire X-band (8–12 GHz) due to the combined effect of multiple loss mechanisms. Full article

(This article belongs to the Section Advanced and Functional Ceramics and Glasses)

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52 pages, 16956 KB

Open AccessEditor’s ChoiceReview

Advances in 2D Group IV Monochalcogenides: Synthesis, Properties, and Applications

by Angel-Theodor Buruiana, Claudia Mihai, Victor Kuncser and Alin Velea

Materials 2025, 18(7), 1530; https://doi.org/10.3390/ma18071530 - 28 Mar 2025

Cited by 2 | Viewed by 1711

Abstract

The field of newly developed two-dimensional (2D) materials with low symmetry and structural in-plane anisotropic properties has grown rapidly in recent years. The phosphorene analog of group IV monochalcogenides is a prominent subset of this group that has attracted a lot of attention [...] Read more.

The field of newly developed two-dimensional (2D) materials with low symmetry and structural in-plane anisotropic properties has grown rapidly in recent years. The phosphorene analog of group IV monochalcogenides is a prominent subset of this group that has attracted a lot of attention because of its unique in-plane anisotropic electronic and optical properties, crystalline symmetries, abundance in the earth’s crust, and environmental friendliness. This article presents a review of the latest research advancements concerning 2D group IV monochalcogenides. It begins with an exploration of the crystal structures of these materials, alongside their optical and electronic properties. The review continues by discussing the various techniques employed for the synthesis of layered group IV monochalcogenides, including both bottom-up methods such as vapor-phase deposition and top-down techniques like mechanical and/or liquid-phase exfoliation. In the final part, the article emphasizes the application of 2D group IV monochalcogenides, particularly in the fields of photocatalysis, photodetectors, nonlinear optics, sensors, batteries, and photovoltaic cells. Full article

(This article belongs to the Section Optical and Photonic Materials)

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10 pages, 3175 KB

Open AccessEditor’s ChoiceArticle

Electric Field-Defined Superlattices in Bilayer Graphene: Formation of Topological Bands in Two Dimensions

by Włodzimierz Jaskólski

Materials 2025, 18(7), 1521; https://doi.org/10.3390/ma18071521 - 28 Mar 2025

Viewed by 777

Abstract

An electric field applied to the Bernal-stacked bilayer graphene opens an energy gap; its reversal in some regions creates domain walls and leads to the appearance of one-dimensional chiral gapless states localized at the walls. Here, we investigate the energy structure of bilayer [...] Read more.

An electric field applied to the Bernal-stacked bilayer graphene opens an energy gap; its reversal in some regions creates domain walls and leads to the appearance of one-dimensional chiral gapless states localized at the walls. Here, we investigate the energy structure of bilayer graphene with superlattice potential defined by an external electric field. The calculations are performed within an atomistic π-electron tight-binding approximation. We study one-dimensional and two-dimensional superlattices formed by arrays of electric-field walls in the zigzag and armchair directions and investigate different field polarizations. Chiral gapless states discretize due to the superlattice potential and transform into minibands in the energy gap. As the main result, we show that the minibands can cross at the Fermi level for some field polarizations. This leads to a new kind of two-dimensional gapless states of topological character that form Dirac-like cones at the crossing points. This also has application potential: changing the field polarization can close the energy gap and change the character of the superlattice from semiconducting to metallic. Full article

(This article belongs to the Special Issue Quantum Transport in Novel 2D Materials and Structures)

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19 pages, 2869 KB

Open AccessEditor’s ChoiceArticle

Low-Cost Chestnut-Based Biocarbons Physically Activated via CO₂ or Steam: Evaluation of the Structural and Adsorption Properties

by Barbara Charmas, Barbara Wawrzaszek, Katarzyna Jedynak and Agata Jawtoszuk

Materials 2025, 18(7), 1497; https://doi.org/10.3390/ma18071497 - 27 Mar 2025

Cited by 1 | Viewed by 777

Abstract

The aim of this paper was to obtain activated biocarbons from the natural biomass of horse chestnut seeds (Aesculus hippocastanum) by physical activation with two different activating agents, carbon dioxide and water vapor, and to evaluate their structural and adsorption properties. [...] Read more.

The aim of this paper was to obtain activated biocarbons from the natural biomass of horse chestnut seeds (Aesculus hippocastanum) by physical activation with two different activating agents, carbon dioxide and water vapor, and to evaluate their structural and adsorption properties. The effect of the pyrolysis atmosphere on the surface development and porosity as well as the structure and adsorption properties of the materials in relation to the selected organic adsorbates (tetracycline (TC), naproxen (NPX), and methyl orange (MO)), which may constitute a potential contamination of the aquatic environment, was evaluated. Activated biocarbons were characterized using N₂ low-temperature adsorption/desorption, Raman and FT-IR spectroscopy, and thermogravimetric analysis (TGA). The nature of the surface (pH_pzc and Boehm titration) was also studied. Micro/mesoporous biocarbons were obtained with an S_BET area in the range of ~534 to 646 m²/g, in which micropores constituted ~70%. It was proved that the obtained materials are characterized by high adsorption values (~120 mg/g, ~150 mg/g, and ~252 mg/g) and removal rates %R (~80%, ~95%, and ~75%) for TC, NPX, and MO, respectively. The results indicate that chestnut-derived activated biocarbons are a promising, cost-effective and environmentally friendly alternative for removing organic contaminants from aqueous solutions. Future research should focus on optimizing activation parameters and assessing the long-term performance of adsorbents. Full article

(This article belongs to the Special Issue Carbonaceous Materials: Fabrication, Characterization and Applications)

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28 pages, 4096 KB

Open AccessEditor’s ChoiceArticle

Spontaneous and Piezo Polarization Versus Polar Surfaces: Fundamentals and Ab Initio Calculations

by Pawel Strak, Pawel Kempisty, Konrad Sakowski, Jacek Piechota, Izabella Grzegory, Eva Monroy, Agata Kaminska and Stanislaw Krukowski

Materials 2025, 18(7), 1489; https://doi.org/10.3390/ma18071489 - 26 Mar 2025

Cited by 2 | Viewed by 901

Abstract

In this study, the fundamental properties of spontaneous and piezo polarization and surface polarity were defined. It was demonstrated that the Landau definition of polarization as a dipole density could be used in infinite systems. Differences between bulk polarization and surface polarity were [...] Read more.

In this study, the fundamental properties of spontaneous and piezo polarization and surface polarity were defined. It was demonstrated that the Landau definition of polarization as a dipole density could be used in infinite systems. Differences between bulk polarization and surface polarity were distinguished, thus creating a clear identification of both components. This identification is in agreement with numerous experimental data—red shift presence and absence for wurtzite and zinc blende multiquantum wells (MQWs), respectively. A local model of spontaneous polarization was created and used to calculate spontaneous polarization as electric dipole density. The proposed local model correctly predicted the c-axis spontaneous polarization values of nitride wurtzite semiconductors. In addition, the model’s results are in accordance with a polarization equal to zero for the zinc blende lattice. The spontaneous polarization values obtained for all wurtzite III nitrides are in basic agreement with earlier calculations using the Berry phase. Ab initio calculations of wurtzite nitride superlattices in Heyd–Scuseria–Ernzerhof (HSE) approximation were performed to derive polarization-induced fields in coherently strained lattices, showing good agreement with the polarization values. Strained superlattice data were used to determine the piezoelectric parameters of wurtzite nitrides, obtaining values that are in basic agreement with earlier data. Zinc blende superlattices were also modeled using ab initio HSE calculations, showing results that are in agreement with the absence of polarization in all nitrides in zinc blende symmetry. Full article

(This article belongs to the Special Issue Advances in Density Functional Theory (DFT) Studies of Solids (Second Volume))

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17 pages, 7854 KB

Open AccessEditor’s ChoiceArticle

Understanding Polysiloxane Polymer to Amorphous SiOC Conversion During Pyrolysis Through ReaxFF Simulation

by Kathy Lu and Harrison Chaney

Materials 2025, 18(7), 1412; https://doi.org/10.3390/ma18071412 - 22 Mar 2025

Viewed by 906

Abstract

A significant challenge during the polymer-to-ceramic pyrolysis conversion is to understand the polymer-to-ceramic atomic evolution and correlate the composition changes with the precursor molecular structures, pyrolysis conditions, and resulting ceramic characteristics. In this study, a Reactive Force Field (ReaxFF) simulation approach has been [...] Read more.

A significant challenge during the polymer-to-ceramic pyrolysis conversion is to understand the polymer-to-ceramic atomic evolution and correlate the composition changes with the precursor molecular structures, pyrolysis conditions, and resulting ceramic characteristics. In this study, a Reactive Force Field (ReaxFF) simulation approach has been used to simulate silicon oxycarbide (SiOC) ceramic formation from four different polysiloxane precursors. For the first time, we show atomically that pyrolysis time and temperature proportionally impact the new Si-O rich and C rich cluster sizes as well as the composition separation of Si-O from C. Polymer side groups have a more complex effect on the Si-O and C cluster separation and growth, with ethyl group leading to the most Si-O cluster separation and phenyl group leading to the most C cluster separation. We also demonstrate never-before correlations of gas release with polymer molecular structures and functional groups. CH₄, C₂H₆, C₂H₄, and H₂ are preferentially released from the pyrolyzing systems. The sequence is determined by the polymer molecular structures. This work is the first to atomically illustrate the innate correlations between the polymer precursors and pyrolyzed ceramics. Full article

(This article belongs to the Special Issue Structural, Thermal, Electrical, and Electrochemical Properties of Novel Ceramics)

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12 pages, 4236 KB

Open AccessEditor’s ChoiceArticle

Capacitance and Dielectric Properties of Spin-Coated Silk Fibroin Thin Films for Bioelectronic Capacitors

by Jongyun Choi, Seung Hun Lee, Taehun Kim, Kyungtaek Min and Sung-Nam Lee

Materials 2025, 18(7), 1408; https://doi.org/10.3390/ma18071408 - 22 Mar 2025

Viewed by 962

Abstract

Silk fibroin, a biocompatible and flexible biopolymer derived from Bombyx mori silkworms, has shown promise in bioelectronics, due to its adjustable dielectric properties. This study investigates the influence of spin coating parameters on the optical, electrical, and dielectric properties of thin silk fibroin [...] Read more.

Silk fibroin, a biocompatible and flexible biopolymer derived from Bombyx mori silkworms, has shown promise in bioelectronics, due to its adjustable dielectric properties. This study investigates the influence of spin coating parameters on the optical, electrical, and dielectric properties of thin silk fibroin films. Silk fibroin solutions were spin coated onto indium tin oxide (ITO)/glass substrates at speeds ranging from 1000 to 7000 revolutions per minute (RPM), resulting in films with thicknesses that varied from 264.8 nm to 81.9 nm. Atomic force microscopy analysis revealed that the surface roughness remained consistent at approximately 1.5 nm across all the spin coating speeds, while the film thickness decreased with the increasing spin speed. Ultraviolet (UV)–visible spectroscopy showed that the transmittance at 550 nm increased from 81.2% at 1000 RPM to 93.8% at 7000 RPM, and the optical bandgap widened from 3.82 eV at 1000 RPM to 3.92 eV at 7000 RPM, which was attributed to reduced molecular packing and quantum confinement effects. Electrical characterization showed that thinner films (a spin speed of 5000–7000 RPM) exhibited a 15-fold increase in the leakage current, rising from 2.99 pA at 1000 RPM to 44.9 pA at 7000 RPM, and a decrease in resistance from 334 GΩ at 1000 RPM to 22.2 GΩ at 7000 RPM. The capacitance–voltage measurements indicated a 4-fold increase in voltage-dependent capacitance for thinner films, with capacitance values increasing from 36 pF at 1000 RPM to 176 pF at 7000 RPM. Dielectric loss analysis revealed that thinner films experienced higher energy dissipation at low frequencies (tan δ of 0.041 at 0.01 MHz for 7000 RPM), but lower losses at high frequencies (tan δ of 0.123 at 1 MHz for 7000 RPM). These findings emphasize the importance of film thickness control in optimizing the performance of silk fibroin-based bioelectronic devices. Full article

(This article belongs to the Special Issue Advanced and Smart Materials in Photoelectric Applications)

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18 pages, 74287 KB

Open AccessEditor’s ChoiceArticle

Graining and Texturing of Metal Surfaces by Picosecond Laser Treatment

by Carmelo Corsaro, Fortunato Neri, Paolo Maria Ossi, Domenico Bonanno, Priscilla Pelleriti and Enza Fazio

Materials 2025, 18(7), 1398; https://doi.org/10.3390/ma18071398 - 21 Mar 2025

Viewed by 1093

Abstract

Different approaches have been proposed to control the tribological behavior of materials under different conformal and non-conformal contact conditions with influenced surface texturing. The ever-increasing demand to improve material friction, erosion wear, and adhesion bond strength of coatings is a major concern for [...] Read more.

Different approaches have been proposed to control the tribological behavior of materials under different conformal and non-conformal contact conditions with influenced surface texturing. The ever-increasing demand to improve material friction, erosion wear, and adhesion bond strength of coatings is a major concern for the contact interface of surfaces. Laser texturing is considered a promising approach to tuning materials’ tribological properties. The latter are strongly influenced by the texture density and shape imprinted on the engineered materials and vary in dry or lubricating conditions. In this work, the physicochemical properties of picosecond laser-textured surfaces of metallic materials have been systematically analyzed. Specifically, the wettability character of laser-textured materials was correlated with their morphological/compositional features. Full article

(This article belongs to the Section Materials Physics)

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11 pages, 3461 KB

Open AccessEditor’s ChoiceArticle

Effects of Multi-Fluorinated Liquid Crystals with High Refractive Index on the Electro-Optical Properties of Polymer-Dispersed Liquid Crystals

by Yunxiao Ren and Wei Hu

Materials 2025, 18(7), 1406; https://doi.org/10.3390/ma18071406 - 21 Mar 2025

Cited by 1 | Viewed by 781

Abstract

Polymer-dispersed liquid crystals (PDLCs) are composite materials, in which LCs are dispersed in the form of microdroplets in a polymer matrix. As a composite material, its electro-optical properties are affected by many factors such as molecular structure, composition, and the microstructure of the [...] Read more.

Polymer-dispersed liquid crystals (PDLCs) are composite materials, in which LCs are dispersed in the form of microdroplets in a polymer matrix. As a composite material, its electro-optical properties are affected by many factors such as molecular structure, composition, and the microstructure of the LCs and polymers. In this work, PDLC films were prepared based on the thiol-ene click reaction, and effects of refractive indexes of polymers and LCs on their electro-optical properties were studied. The refractive indexes of the polymer matrix are adjusted by controlling the content of sulfur element, and those of the LCs are adjusted by adding multi-fluorinated LCs with high refractive index. By regulating the refractive indexes of the polymer matrix and LCs, the maximum transmittance of the film is raised and the viewing angle of the film is also extended. This work could afford some ideas for the directional regulation of the viewing angles and the electro-optical properties of the PDLC film. Full article

(This article belongs to the Special Issue Advanced and Smart Materials in Photoelectric Applications)

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15 pages, 5604 KB

Open AccessEditor’s ChoiceArticle

Dynamic Response and Energy Absorption of Lattice Sandwich Composite Structures Under Underwater Explosive Load

by Xiaolong Zhang, Shengjie Sun, Xiao Kang, Zhixin Huang and Ying Li

Materials 2025, 18(6), 1317; https://doi.org/10.3390/ma18061317 - 17 Mar 2025

Cited by 2 | Viewed by 869

Abstract

This study investigates the underwater explosion resistance of aluminum alloy octet-truss lattice sandwich structures using shock tube experiments and LS-DYNA simulations. A systematic analysis reveals key mechanisms influencing protective performance. The sandwich configuration mitigates back plate displacement through quadrilateral inward deformation, exhibiting phased [...] Read more.

This study investigates the underwater explosion resistance of aluminum alloy octet-truss lattice sandwich structures using shock tube experiments and LS-DYNA simulations. A systematic analysis reveals key mechanisms influencing protective performance. The sandwich configuration mitigates back plate displacement through quadrilateral inward deformation, exhibiting phased deformation responses between face plates and back plates mediated by lattice interactions. Increasing the lattice relative density from 0.1 to 0.3 reduces maximum back plate displacement by 22.2%. While increasing the target plate thickness to 1.5 mm reduces displacement by 47.6%, it also decreases energy absorption efficiency by 20% due to limited plastic deformation. Fluid–structure interaction simulations correlate well with 3D-DIC deformation measurements. The experimental results demonstrate the exceptional impact energy absorption capacity of the octet-truss lattice and highlight the importance of stiffness-matching strategies for enhanced energy dissipation. These findings provide valuable insights for optimizing the design of underwater protection structures. Full article

(This article belongs to the Special Issue Mechanical Properties and Structural Reliability of Advanced Materials)

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17 pages, 3853 KB

Open AccessEditor’s ChoiceArticle

Analysis of the Structural, Chemical, and Mechanical Characteristics of Polyurethane Foam Infused with Waste from Thermal Processing

by Anna Magiera, Monika Kuźnia and Wojciech Jerzak

Materials 2025, 18(6), 1327; https://doi.org/10.3390/ma18061327 - 17 Mar 2025

Cited by 3 | Viewed by 632

Abstract

The continuous generation of agricultural, industrial, and urban waste necessitates effective waste management strategies. One promising approach is incorporating these residues as fillers in polymer composites. This study investigated the influence of coal processing-derived fillers, specifically microspheres and fluidized-bed combustion fly ash, on [...] Read more.

The continuous generation of agricultural, industrial, and urban waste necessitates effective waste management strategies. One promising approach is incorporating these residues as fillers in polymer composites. This study investigated the influence of coal processing-derived fillers, specifically microspheres and fluidized-bed combustion fly ash, on the structure and properties of composite rigid polyurethane foam. Polyurethane foams were produced through manual mixing and casting, with composite foams containing a combination of 5% microspheres and 5–15% fly ash by weight. The analysis of the samples investigated their structural, thermal, and mechanical properties. The samples consistently displayed predominantly pentagonal, regularly shaped cells. Infrared spectroscopy revealed no observable chemical bonding between the matrix and filler materials. Mechanical analysis was performed to evaluate the materials’ characteristics, revealing significant variations in compressive strength and Young’s modulus values. The results indicate that the addition of fillers did not impact the cellular and chemical composition of the polyurethane matrix. Furthermore, the composite material specimens were subjected to accelerated aging in a laboratory dryer and outdoor exposure in order to assess their thermal stability. This analysis revealed notable alterations in both the cellular composition and mechanical properties of the composite foam materials. Full article

(This article belongs to the Special Issue Research on Thermal Stability and Degradation of Polymers and Their Potential Use in a Circular Economy Development)

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17 pages, 3101 KB

Open AccessEditor’s ChoiceArticle

Removal of Per- and Polyfluoroalkyl Substances Using Commercially Available Sorbents

by Zhiming Zhang, Sevda Joudiazar, Anshuman Satpathy, Eustace Fernando, Roxana Rahmati, Junchul Kim, Giacomo de Falco, Rupali Datta and Dibyendu Sarkar

Materials 2025, 18(6), 1299; https://doi.org/10.3390/ma18061299 - 15 Mar 2025

Cited by 3 | Viewed by 3349

Abstract

Per- and polyfluoroalkyl substances (PFAS) are persistent organic pollutants of growing environmental and human health concern, widely detected across various environmental compartments. Effective remediation strategies are essential to mitigate their widespread impacts. This study compared the performance of two types of commercially available [...] Read more.

Per- and polyfluoroalkyl substances (PFAS) are persistent organic pollutants of growing environmental and human health concern, widely detected across various environmental compartments. Effective remediation strategies are essential to mitigate their widespread impacts. This study compared the performance of two types of commercially available sorbent materials, granular activated carbon (GAC, Filtrasorb-400) and organoclays (OC-200, and modified organoclays Fluoro-sorb-100 and Fluoro-sorb-200) for the removal of three representative PFAS compounds: perfluorooctanoic acid (PFOA), perfluorononanoic acid (PFNA), and perfluorooctane sulfonic acid (PFOS) from water. Both organoclays and modified organoclays outperformed GAC, likely due to electrostatic interactions between the anionic PFAS compounds and the cationic functional groups of the modified organoclays. A pseudo-second-order kinetic model best described the rapid sorption kinetics of PFOA, PFNA, and PFOS. For PFOA, OC-200 demonstrated the highest adsorption capacities (q_max = 47.17 µg/g). For PFNA and PFOS, Fluoro-sorb-100 was the most effective sorbent, with q_max values at 99.01 µg/g and 65.79 µg/g, respectively. Desorption studies indicated that the sorption of the three PFAS compounds on these commercially available sorbents was largely irreversible. This study highlights the effectiveness and sorption capacities of different types of commercial sorbents for PFAS removal and offers valuable insights into the selection of reactive media for PFAS removal from water under environmentally relevant conditions. Full article

(This article belongs to the Special Issue Advanced Nanoporous and Mesoporous Materials)

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12 pages, 1759 KB

Open AccessEditor’s ChoiceArticle

One-Pot Synthesis of Pd@Pt Core-Shell Icosahedron for Efficient Oxygen Reduction

by Zisheng Tang, Dafu Zhao, Xiaoqian Wang, Yanhui Jiao, Manrui Liu, Chengqi Liu, Qi Zhang, Shujing Ren and Yong Liu

Materials 2025, 18(6), 1279; https://doi.org/10.3390/ma18061279 - 13 Mar 2025

Viewed by 1310

Abstract

Enhancing the limited utilization and overall yield of Pt-based catalysts is essential for advancing proton exchange membrane fuel cell technology. Herein, we report a facile one-pot method that utilizes TEG as both a solvent and a reductant to efficiently synthesize a Pd@Pt core-shell [...] Read more.

Enhancing the limited utilization and overall yield of Pt-based catalysts is essential for advancing proton exchange membrane fuel cell technology. Herein, we report a facile one-pot method that utilizes TEG as both a solvent and a reductant to efficiently synthesize a Pd@Pt core-shell icosahedron. By controlling the surface energy between Pd and Pt precursors, we achieved the formation of Pd@Pt core-shell icosahedra, resulting in a fourfold reduction in reaction time and an eightfold increase in yield. Moreover, the core-shell structures exhibited a significant enhancement in electrocatalytic activity, stability, and Pt utilization efficiency. In comparison to commercial Pt/C, the Pd@Pt core-shell icosahedron exhibited efficient mass activity (MA, 1.54 A mg⁻¹_Pt) and specific activity (SA, 2.24 mA cm⁻²_Pt) at 0.9 V (vs. RHE), while demonstrating excellent stability with minimal loss of activity even after 10,000 potential cycles. The Pd@Pt icosahedra configuration integrates the advantages of multiply twinned nanostructures, leading to rich electrochemical active surface sites and fast charge transport, thereby improving its catalytic performance and long-term stability during electrocatalytic reactions. Full article

(This article belongs to the Special Issue Photoelectric and Catalytic Properties of Nanomaterials and Low-Dimensional Structures)

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13 pages, 3445 KB

Open AccessEditor’s ChoiceArticle

Evaluating the Role of Unit Cell Multiplicity in the Acoustic Response of Phononic Crystals Using Laser-Plasma Sound Sources

by Emmanouil Kaniolakis Kaloudis, Konstantinos Kaleris, Nikos Aravantinos-Zafiris, Michael Sigalas, Dionysios T. G. Katerelos, Vasilis Dimitriou, Makis Bakarezos, Michael Tatarakis and Nektarios A. Papadogiannis

Materials 2025, 18(6), 1251; https://doi.org/10.3390/ma18061251 - 12 Mar 2025

Cited by 1 | Viewed by 922

Abstract

Acoustic metamaterials and phononic crystals are progressively consolidating as an important technology that is expected to significantly impact the science and industry of acoustics in the coming years. In this work, the impact of unit cell multiplicity on the spectral features of the [...] Read more.

Acoustic metamaterials and phononic crystals are progressively consolidating as an important technology that is expected to significantly impact the science and industry of acoustics in the coming years. In this work, the impact of unit cell multiplicity on the spectral features of the acoustic response of phononic crystals is systematically studied using the recently demonstrated laser-plasma sound source characterization method. Specifically, by exploiting the advantages of this method, the impact of the number of repeated unit cells on the depth of the phononic band gaps and the passband spectral features across the entire audible range is demonstrated. These experimental findings are supported by specially developed computational simulations accounting for the precise structural characteristics of the studied phononic crystals and are analysed to provide a phenomenological understanding of the underlying physical mechanism. It is shown that by increasing the unit cell multiplicity, the bandgaps deepen and the number of resonant peaks in the crystal transmission zones increases. The resonant mode shapes are computationally investigated and interpreted in terms of spherical harmonics. This study highlights the tunability and design flexibility of acoustic components using phononic crystals, opening new paths towards applications in the fields of sound control and noise insulation. Full article

(This article belongs to the Special Issue Advances in Modelling and Simulation of Materials in Applied Sciences)

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22 pages, 12982 KB

Open AccessEditor’s ChoiceArticle

Effect of Hydrothermal Coatings of Magnesium AZ31 Alloy on Osteogenic Differentiation of hMSCs: From Gene to Protein Analysis

by Viviana Costa, Lavinia Raimondi, Simone Dario Scilabra, Margot Lo Pinto, Daniele Bellavia, Angela De Luca, Pasquale Guglielmi, Angela Cusanno, Luca Cattini, Lia Pulsatelli, Matteo Pavarini, Roberto Chiesa and Gianluca Giavaresi

Materials 2025, 18(6), 1254; https://doi.org/10.3390/ma18061254 - 12 Mar 2025

Cited by 4 | Viewed by 874

Abstract

An Mg-based alloy device manufactured via a superplastic forming process (Mg-AZ31+SPF) and coated using a hydrothermal method (Mg AZ31+SPF+HT) was investigated as a method to increase mechanical and osteointegration capability. The cell viability and osteointegrative properties of alloy-derived Mg AZ31+SPF and Mg AZ31+SPF+HT [...] Read more.

An Mg-based alloy device manufactured via a superplastic forming process (Mg-AZ31+SPF) and coated using a hydrothermal method (Mg AZ31+SPF+HT) was investigated as a method to increase mechanical and osteointegration capability. The cell viability and osteointegrative properties of alloy-derived Mg AZ31+SPF and Mg AZ31+SPF+HT extracts were investigated regarding their effect on human mesenchymal stem cells (hMSCs) (maintained in basal (BM) and osteogenic medium (OM)) after 7 and 14 days of treatment. The viability was analyzed through metabolic activity and double-strand DNA quantification, while the osteoinductive effects were evaluated through qRT-PCR, osteoimage, and BioPlex investigations. Finally, a preliminary liquid mass spectrometry analysis was conducted on the secretome of hMSCs. Biocompatibility analysis revealed no toxic effect on cells’ viability or proliferation during the experimental period. A modulation effect was observed on the osteoblast pre-commitment genes of hMSCs treated with Mg-AZ31+SPF+HT in OM, which was supported by mineralization nodule analysis. A preliminary mass spectrometry investigation highlighted the modulation of protein clusters involved in extracellular exosomes, Hippo, and the lipid metabolism process. In conclusion, our results revealed that the Mg AZ31+SPF+HT extracts can modulate the canonical and non-canonical osteogenic process in vitro, suggesting their possible application in bone tissue engineering. Full article

(This article belongs to the Special Issue Nanocomposite High Performance Alloys)

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10 pages, 2639 KB

Open AccessEditor’s ChoiceCommunication

A High-Performance All-Carbon Diamond Pixel Solar-Blind Detector with In Situ Converted Graphene Electrodes

by Mingxin Jiang, Zhenglin Jia, Mengting Qiu, Xingqiao Chen, Jiayi Cai, Mingyang Yang, Yi Shen, Chaoping Liu, Kuan W. A. Chee, Nan Jiang, Kazuhito Nishimura, Qingning Li, Qilong Yuan and He Li

Materials 2025, 18(6), 1222; https://doi.org/10.3390/ma18061222 - 10 Mar 2025

Viewed by 1067

Abstract

Solar-blind ultraviolet detectors, known for their low background noise and high sensitivity, have garnered significant attention in various applications such as space communications, ozone layer monitoring, guidance applications, and flame detection. Pixel photodetectors, as the cornerstone of imaging technology in this field, have [...] Read more.

Solar-blind ultraviolet detectors, known for their low background noise and high sensitivity, have garnered significant attention in various applications such as space communications, ozone layer monitoring, guidance applications, and flame detection. Pixel photodetectors, as the cornerstone of imaging technology in this field, have become a focal point of research in recent years. In this work, a solar-blind photodetector with a 6 × 6 planar pixel array was fabricated on single-crystal diamond substrate, utilizing in situ conversed graphene electrodes. The graphene electrodes achieved exceptional Ohmic contact with the diamond surface, boasting a remarkably low specific contact resistance of 6.73 × 10⁻⁵ Ω·cm². The diamond pixel detector exhibited high performance consistency with an ultra-low dark current ranging from 10⁻¹¹ to 10⁻¹² A and a photocurrent of 10⁻⁸~10⁻⁹ A under 222 nm illumination with a bias of 10 V. This work not only demonstrates the feasibility of fabricating all-carbon solar-blind photodetectors on diamond but also highlights their potential for achieving high spatial resolution in solar-blind image detection. Full article

(This article belongs to the Section Electronic Materials)

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