Journal of Materials Science最新文献

Maraging steels are ultra-high-strength alloys whose microstructure and mechanical properties are predominantly determined by aging temperature. This study systematically compares the aging response (at 450, 500, 550 °C) of Co-containing and Co-free Mo-modified grades. Results reveal that Co significantly enhances precipitation kinetics and refines precipitate distribution, while effectively suppressing the formation of reverted austenite. This alters the strength–toughness balance, with Co-containing alloys achieving higher strength and Co-free alloys exhibiting superior ductility. Mechanical testing identified 500 °C as the optimum aging temperature. Strengthening mechanism analysis confirmed that Co promotes a synergistic combination of matrix and precipitation strengthening. This work elucidates Co’s governing role in precipitation and phase transformation, providing a foundation for designing high-performance maraging steels.

Manganese dioxide (MnO₂₎ holds significant promise for asymmetric supercapacitors (ASCs) owing to its abundant natural resources, environmental compatibility, and high theoretical specific capacity. However, its practical electrochemical performance is often substantially limited by poor intrinsic electrical conductivity, resulting in actual capacity values far below the theoretical expectations. In this work, we propose an effective strategy to address these limitations by constructing a rationally designed MnO₂@NiMo-LDH heterostructure. The hybrid MnO₂@NiMo-LDH electrode exhibits a remarkable specific capacity of 622.8 C g⁻¹ at 1 A g⁻¹, significantly surpassing that of pristine MnO₂ (148.0 C g⁻¹) and NiMo-LDH (426.4 C g⁻¹). Furthermore, an asymmetric supercapacitor device assembled with MnO₂@NiMo-LDH as the positive electrode and activated carbon (AC) as the negative electrode achieves an extended voltage window of 1.7 V and an energy density of 36.4 Wh/kg at a power density of 845.4 W/kg. Notably, the device demonstrates excellent cyclability, retaining 85.45% of its initial capacitance after 10,000 cycles at 2 A g⁻¹. This study not only highlights MnO₂@NiMo-LDH as a high-performance electrode material but also provides a generalizable design strategy for developing advanced MnO₂-based supercapacitor electrodes with enhanced electrochemical properties.

The accumulation of lead ions in industrial wastewater poses a long-term threat to ecosystems and health. Traditional detection techniques often fail to maintain sensitivity, selectivity, and signal stability in complex matrices. This paper builds a multilevel conductive composite structure based on covalent organic framework, platinum nanoparticles, and carboxylated multiwalled carbon nanotubes, and also builds an enhanced luminescent interface with gold nanoparticles and boron nitride quantum dots to improve electronic transmission and target recognition. The experimental results show a good linear relationship in the range of 0.005 to 50 ng/mL, and the luminescent signal reaches about 14,000 a.u. The interfacial resistance decreases to 0.78 kΩ, and the system gives a clear charge response after exposure to lead ions. The spiked recovery rate is up to 99.32% in wastewater samples and reaches a signal retention of 93.13% after 30 days. All the results indicate that the composite structure supplies high sensitivity, good selectivity, and strong stability in the detection of lead ions, offering an effective technical approach toward monitoring heavy metals in such complex wastewater.

Hexagonal boron nitride (h-BN) has received more attention due to its good stability and wide applications. A comprehensive study of h-ScN materials similar to h-BN has been performed using density functional theory, covering aspects from electronic structure to physical properties. The band gap calculated with the HSE06 (Hybrid Screened Exchange 06) functional of VASP (Vienna Ab initio Simulation Package) is 2.903 eV. From the perspectives of phonon spectra, elastic constants matrix, and thermodynamics, h-ScN material exhibits lattice dynamical, mechanical, and thermal stability. The carrier mobilities in ScN are generally high but anisotropic, with a range of 30–6329 cm² V⁻¹ s⁻¹. Subsequently, the property regulation of the sheet structure, ribbon structure, and tube structure of the material was investigated. So ScN materials have potential applications in fields such as electronics, optoelectronics, and stress sensors.

The induction of cuproptosis, a recently identified form of copper-dependent non-apoptotic cell death, offers a promising strategy to enhance the efficacy of chemotherapeutic antitumor treatments. However, efficiently delivering copper ions into tumor mitochondria to robustly trigger cuproptosis while simultaneously potentiating chemotherapy remains a major challenge. Herein, we develop a cuproptosis-inducing nanodrug constructed via amino acid-assisted cooperative coordination self-assembly of copper ion, the copper ionophore elesclomol (ES), and the chemotherapeutic agent docetaxel (DTX) to augment chemo-immunotherapy of prostate cancer. Once internalized by tumor cells, the obtained nanodrugs gradually degrade to release copper ions and ES, which together promote the aggregation of lipoylated proteins and the depletion of Fe–S cluster proteins, thereby activating cuproptosis and amplifying DTX-mediated chemotherapy. Moreover, the nanodrugs elicit robust immunogenic cell death through the combined actions of cuproptosis and DTX-induced apoptosis, further boosting antitumor immune responses. Overall, the multicomponent co-assembled nanodrugs demonstrate excellent antitumor activity both in vitro and in vivo by integrating cuproptosis induction, chemotherapy enhancement, and immune activation, highlighting their strong potential for clinical translation in prostate cancer therapy.

In this study, we utilize first-principles calculations to conduct a systematic exploration into how the electrical and optical properties evolve when single-layer SnS₂, single-layer SnSe₂, as well as their SnS₂/SnSe₂ heterojunction structures, are subjected to shear strain. To ensure structural stability, we performed a comprehensive assessment by analyzing the phonon spectrum and calculating the binding energy. Among the various configurations examined, the one displaying the lowest binding energy was chosen for subsequent in-depth investigation. Results demonstrate that as shear deformation increases, the bandgap values of all three systems decrease. Notably, at 8% shear strain, the bandgap of both the SnSe₂ system and SnS₂/SnSe₂ heterojunction system reduces to 0 eV, resulting in their transition from semiconductors to metals. Optically, in the low-energy region, increased shear deformation enhances light reflection and absorption capabilities. The dielectric function exhibits a pronounced trend of “increased polarization enhancement in the low-energy region and weakened response in the mid-to-high-energy regions,” with the interface effect of the SnS₂/SnSe₂ heterojunction amplifying this modulation.

This paper elucidates the anisotropy of the wet etching of single-crystal silicon from an energy perspective through calculation and analysis of activation energies across various crystal planes and exposed atoms. Firstly, the study determines activation energies of various crystal planes based on etching rates under varying temperature conditions using the Arrhenius equation, analyzing the relationship between these activation energies and etching rates. Subsequently, the temperature dependence of the removal probability equation in the Monte Carlo simulation model is modified to enable simulations under various temperature conditions. Finally, the modified removal probability equation facilitates the calculation of removal probabilities of exposed atoms at various temperatures, determining activation energies of various types of exposed atoms and analyzing their influence on etching rates of crystal planes. This research advances the understanding of the mechanism of anisotropic wet etching of single-crystal silicon and enhances the optimization of its wet etching process.

Iron-chromium redox flow batteries (ICRFBs) have emerged as a promising candidate for large-scale energy storage due to their cost-effectiveness, long cycle life, power-energy decoupling, and inherent safety. However, conventional ICRFBs using acidic FeCl₂ + CrCl₃ + HCl electrolytes face critical challenges, including severe material corrosion, active species cross-contamination, and parasitic hydrogen evolution reactions. To address these issues, we propose a neutral chelated Fe/Cr electrolyte system utilizing the identical ligand, 1,3-diaminopropanetetraacetic acid (DTPA), for both half-cells. This symmetric ligand design effectively suppresses metal ion crossover while enhancing redox kinetics, as confirmed by Fourier transform infrared (FTIR) and ultraviolet–visible (UV–vis) spectroscopy. The DTPA-complexed electrolytes exhibit high solubility (up to 1.0 mol/L) and environmental benignity, eliminating the need for corrosive acids. The resulting ICRFB demonstrates outstanding performance: a discharge energy density of 12.1 Wh/L, an average capacity decay rate of 0.13% per cycle over 300 cycles, and a coulombic efficiency approaching 100% at 50 mA/cm², with a round-trip energy efficiency of 60%. These metrics are comparable to those of traditional acidic systems but with significantly reduced material degradation and operational risks. Our work validates the chelation strategy as a viable pathway to develop low-cost, long-lifetime ICRFBs, accelerating their practical deployment in grid-scale energy storage applications.

Graphical Abstract

The fabrication of sputtered indium tin oxide (ITO) nanorod arrays offers a promising and economical approach to improving light management in photovoltaic devices. In this study, we introduce a novel light-trapping approach using a sputtered ITO nanorod array as a substitute for traditional surface texturing. We successfully fabricated a hydrogenated amorphous silicon (a-Si:H) p-i-n solar cell on the ITO nanorod substrate and compared its performance to a standard reference device. The ITO nanorods, grown at 320 °C, exhibited excellent optical properties, with a diffused-to-total transmitted light ratio exceeding 50% at 400 nm and over 20% at 800 nm, indicating effective scattering across a broad spectral range. The nanorod-driven a-Si:H solar cell, using a significantly thinner intrinsic absorber layer of just 150 nm (compared to the conventional 300 nm), achieved a power conversion efficiency of 4.97%. Furthermore, it achieved a notable short-circuit current density (J_sc) of 12.07 mA/cm², significantly exceeding that of the planar reference device. These results evidently validate the effectiveness of ITO nanorod arrays in enhancing light absorption and charge collection and highlight their potential as an advanced front transparent conductive oxide (TCO) architecture for advanced silicon-based thin-film solar cells.

The purpose of this study is to quantify the mechanical and tribological properties of graphene-reinforced platinum nanocomposites (Gr/Pt NCs) using molecular dynamics (MD) simulations. A layered (plate-type) simulation model was employed to accurately simulate surface-to-surface sliding tribology and tensile properties, utilizing a hybrid force field combining quantum-corrected Sutton–Chen (Pt–Pt), Stillinger–Weber (C–C), and Morse (Pt-C) potentials. The primary objectives are to investigate the effect of the number of graphene layers (1 to 5), corresponding to a graphene content of 1.13 wt% to 1.87 wt%, on mechanical strength, and to evaluate the influence of temperature, vertical load, and sliding velocity on tribological behavior. This study offers the first comprehensive molecular dynamics investigation quantifying the coupled effects of graphene layer count and temperature on both the mechanical and high-velocity tribological performance of Gr/Pt NCs. Introducing graphene sheets significantly enhances mechanical performance; compared to pure platinum (11.3 GPa), a single-layer Gr/Pt NC exhibits a 64.6% higher yield strength (18.6 GPa) at 300 K. Increasing the number of graphene layers from 1 to 5 further elevates Young’s modulus from 199.3 GPa to 305.9 GPa (53.5%) and raises the ultimate strength from 17.6 GPa to 22.4 GPa (27.3%). Tensile responses show strong agreement with theoretical predictions, confirming the superior performance of the nanocomposites. Tribological analysis reveals that the coefficient of friction (COF) is highly dependent on operating conditions. Higher temperatures reduce friction, lowering the COF from 0.078 at 50 K to 0.004 at 600 K due to thermally activated reduction of adhesive interactions. Although higher vertical loads increase friction force, the COF decreases, indicating an adhesion-dominated nanoscale regime. Sliding velocity also plays a critical role; increasing velocity from 50 m/s to 200 m/s raises the COF from 0.43 to 0.99, with wear initiation observed at 200 m/s. These findings quantify the superior mechanical strength and tunable frictional characteristics of Gr/Pt NCs relative to pure platinum.