Journal of Alloys and Compounds最新文献

{"title":"Bimetallic (NiCo) metal-organic framework nanosheets with ultrafine Ru as bifunctional electrocatalyst for overall water splitting","authors":"Tingxia Wang ,&nbsp;Xiaojiao Yu ,&nbsp;Yingge Zhang ,&nbsp;Tong Yang ,&nbsp;Ziwei Cheng ,&nbsp;Junpeng Li","doi":"10.1016/j.jallcom.2025.181184","DOIUrl":"10.1016/j.jallcom.2025.181184","url":null,"abstract":"<div><div>Constructing metal-support interface and modulating electronic structure are challenging despite the promising potential in boosting electrocatalytic activity for alkaline overall water splitting. Herein, ultrafine Ru nanoparticles coupled with bimetallic (NiCo) metal-organic framework nanosheets fabricated on CC (Ru/NiCo NDC/CC, NDC: 2,6-naphthalenedicarboxylic) were well-designed to achieve the aforementioned strategies. The coupling effect of Ru and NiCo NDC effectively regulated the electronic structure of Ru/NiCo NDC, which facilitated electron transfer and enhanced the intrinsic activity for overall water splitting. The presence of NiCo NDC nanosheets provided larger surface area for anchoring more ultrafine Ru, which significantly increased electrochemically active area, augmenting electrocatalytic activity for alkaline water splitting. Consequently, the optimal Ru/NiCo NDC/CC required low overpotentials of 61 and 59 mV at −10 mA cm⁻² in acidic and alkaline solution, respectively. Additionally, Ru/NiCo NDC/CC electrocatalyst exhibited a superior activity for OER with an overpotential 228 mV at 10 mA cm⁻². Moreover, the water electrolyzer fabricated by Ru/NiCo NDC/CC as bifunctional electrocatalyst delivered a current density of 10 mA cm⁻² at 1.56 V. This work highlights the feasibility of a dual strategy of constructing metal-support and regulating electronic structure in enhancing electrocatalytic performance.</div></div>","PeriodicalId":344,"journal":{"name":"Journal of Alloys and Compounds","volume":"1033 ","pages":"Article 181184"},"PeriodicalIF":5.8,"publicationDate":"2025-05-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144145828","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Microstructure evolution upon directional solidification process of Nb-Si based ultrahigh temperature alloy","authors":"Yunlong Fu,&nbsp;Xiping Guo,&nbsp;Zhuqin Xiao","doi":"10.1016/j.jallcom.2025.181246","DOIUrl":"10.1016/j.jallcom.2025.181246","url":null,"abstract":"<div><div>The microstructure evolution was investigated in the directionally solidified (DS) Nb-22Ti-14.8Si-3Cr (at%) alloy. The directional solidification zone of the DS bar prepared by the crucible integral directional solidification can be divided into initial transient zone, steady state solidification zone and final transient zone from re-melted interface to the top of the DS bar, according to the microstructure characteristics including phase constituent, crystallographic orientation, microstructure morphology, quantitative metallography and composition with distance away from the bottom of the DS bar. In the initial transient zone, the increase of growth rate leads to the decrease of the average size of eutectic cells, average interlamellar spacing and average size of primary γ-Nb₅Si₃. The decrease of the area fraction of primary γ-Nb₅Si₃ in the transverse section is attributed to preferential growth among the primary γ-Nb₅Si₃ blocks. In the steady state solidification zone, the microstructures are well aligned and the halo Nb_SS (Nb solid solution) mainly exists. In the final transient zone, the area fraction and size of primary γ-Nb₅Si₃ increase as the hypereutectic degree increases with the accumulation of Ti, Cr, and Si contents. The contents of Ti and Cr in the DS bar increase in the initial transient zone, remain at a stable level in the steady state solidification zone, and then increase in the final transient zone with the distance away from the bottom of the DS bar.</div></div>","PeriodicalId":344,"journal":{"name":"Journal of Alloys and Compounds","volume":"1033 ","pages":"Article 181246"},"PeriodicalIF":5.8,"publicationDate":"2025-05-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144137070","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of Solid-Solution Treatment and Cooling Method on Texture Evolution and Properties of Super Invar Alloy Fabricated by Laser Powder Bed Fusion","authors":"Renjie Zhao, Haihui Liu, Kai Feng, Zhuguo Li, Renbiao Xie","doi":"10.1016/j.jallcom.2025.181191","DOIUrl":"https://doi.org/10.1016/j.jallcom.2025.181191","url":null,"abstract":"Tailored heat treatment is crucial for achieving the desired low coefficient of thermal expansion (CTE) and high elastic modulus (&lt;em&gt;E&lt;/em&gt;) of laser powder bed fusion (LPBF) processed Super Invar alloy (Fe-32Ni-4Co) in semiconductor equipment and other precision devices. This paper thoroughly investigates the effect of solid-solution treatment (at 830 ℃ and 1030 ℃) and cooling method (Furnace cooling, air cooling, oil cooling and water quenching) on the microstructures, mechanical properties, magnetic properties and thermal expansion behaviors of LPBF manufactured Super Invar alloy samples. Faster cooling rate is favorable for the development of stronger textures of Copper components, while WQ and particularly FC can lead to Goss component enhancement. The as-built Super Invar alloy samples contain relatively high residual compressive stresses. Solid-solution treatment at higher temperature and faster cooling rates can more effectively relieve these compressive residual stresses and induce higher internal tensile stresses in the interior. Solid-solution treatment at 1030 ℃ results in lower strength, hardness and elastic modulus than at 830 ℃. The hardness, strength, elastic modulus and average CTE within 30~100 ℃ are generally negatively correlated with cooling rate despite the abnormal enhancement in water-quenched samples. Attributed to water-quenching-induced &lt;111&gt; and &lt;110&gt; texture generation, the water-quenched samples, particularly solution-treated at 1030 ℃, exhibit notable rigidity recovery. Strong magnetostriction effect, which may be attributed to the poor elastic property, is observed within the oil-cooled samples showing the lowest thermal expansions. A negative correlation between Curie temperature and cooling rate can be clearly identified. The vertically-measured saturation magnetization variation generally follows the intensity variation of dominant Goss textures of the columnar grains within side surfaces, while the horizontally-measured saturation magnetization value is positively correlated with the intensity of notable Copper textures within the equiaxed-grain zone. The furnace-cooled samples solution-treated at 830 ℃ exhibit the highest rigidity (Vertical &lt;em&gt;E&lt;/em&gt;: 155.7&lt;!-- --&gt; &lt;!-- --&gt;GPa. Horizontal &lt;em&gt;E&lt;/em&gt;: 130.5&lt;!-- --&gt; &lt;!-- --&gt;GPa) and strength but even higher CT&lt;em&gt;E&lt;/em&gt;s (above 1.0×10&lt;sup&gt;-6&lt;/sup&gt; °C&lt;sup&gt;-1&lt;/sup&gt;, 30~100 °C) than the standard suggests. The oil-cooled treated samples solution-treated at 830 ℃ possess the lowest CTEs (0.20×10&lt;sup&gt;-6&lt;/sup&gt;~0.40×10&lt;sup&gt;-6&lt;/sup&gt; °C&lt;sup&gt;-1&lt;/sup&gt;, 30~100 °C) at the sacrifice of relatively small &lt;em&gt;E&lt;/em&gt; decline (Vertical &lt;em&gt;E&lt;/em&gt;: 136.6&lt;!-- --&gt; &lt;!-- --&gt;GPa. Horizontal &lt;em&gt;E&lt;/em&gt;: 123.5&lt;!-- --&gt; &lt;!-- --&gt;GPa). The water-quenched ones solution-treated at 1030 °C demonstrate comprehensively acceptable CTEs (0.40×10&lt;sup&gt;-6&lt;/sup&gt;~0.80×10&lt;sup&gt;-6&lt;/sup&gt; °C&lt;sup&gt;-1&lt;/sup&gt;, 30~100 °C) and superior stiffness performance (Vertical &lt;em&gt;E&lt;/em&gt;: 152.4&lt;!-- --&gt; &lt;!-- --&gt;GP","PeriodicalId":344,"journal":{"name":"Journal of Alloys and Compounds","volume":"39 1","pages":""},"PeriodicalIF":6.2,"publicationDate":"2025-05-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144137015","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A-site La-doped PrBaFe2O5+δ Cathode with Enhanced Catalytic Activity for High-Performance Intermediate-Temperature Solid Oxide Fuel Cells","authors":"Duoyu Zhou, Rui Zhang, Songsong Xu, Kenan Yi, Yunhe Zhang, Jianhua Liu, Lina Su, Li Li, Fengyang Yu","doi":"10.1016/j.jallcom.2025.181232","DOIUrl":"https://doi.org/10.1016/j.jallcom.2025.181232","url":null,"abstract":"Double perovskite oxide PrBaFe₂O_5+δ (PBF) as a mixed ion and electron conductor is a promising cathode catalyst for intermediate temperature SOFCs (IT-SOFC). In order to promote its oxygen reduction reaction (ORR) kinetics, an efficient A-site La³⁺ doping strategy was employed to synthesize a series of highly active Pr_1-xLa_xBaFe₂O_5+δ (denoted as PLBFx, x=0.1-0.4) cathodes for IT-SOFCs. The incorporation of La³⁺ into the PBF lattice induces lattice expansion and optimizes the Fe-O-Fe bond, significantly improving oxygen surface exchange kinetics and bulk diffusion process. The optimized PLBF0.2 cathode exhibits the lowest polarization resistance (ASR, 0.029 Ω·cm² at 800 °C, 50% lower than that of un-doped PBF (0.058 Ω·cm²), and a maximum conductivity of 111 S·cm^-1. Moreover, a Ni-YSZ anode-supported single cell with PLBF0.2 cathode delivers a peak power density of 1.565<!-- --> <!-- -->W·cm⁻² at 800 °C, and maintains long-term stability for 200<!-- --> <!-- -->h at 700 °C, surpassing previous reported PBF-based cathodes.","PeriodicalId":344,"journal":{"name":"Journal of Alloys and Compounds","volume":"56 1","pages":""},"PeriodicalIF":6.2,"publicationDate":"2025-05-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144137018","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Anti-Thermal Quenching and Tunable Near-Infrared Luminescence in High-Efficiency Garnet SrLu2Al3ScSiO12: Cr3+, Yb3+ Phosphors for Multifunctional Applications","authors":"Wenchao Gong, Dan Zhang, Kurboniyon Mekhrdod, Chenge Gao, Valery F. Gremenok, Peng Wang, Chonggeng Ma","doi":"10.1016/j.jallcom.2025.181234","DOIUrl":"https://doi.org/10.1016/j.jallcom.2025.181234","url":null,"abstract":"Near-infrared (NIR) phosphor-converted light-emitting diodes (pc-LEDs) have found extensive applications in diverse fields including night vision, medical diagnostics, and plant lighting. However, designing NIR phosphors with large full width at half maximum (FWHM) and high thermal stability remains challenging. In this study, we developed a SrLu₂Al₃ScSiO₁₂: Cr³⁺, Yb³⁺ phosphor (abbreviated as SLASSO: Cr³⁺, Yb³⁺) through a high-temperature solid-state reaction method. The SLASSO: Cr³⁺ samples exhibit two broad absorption bands in the blue light region (~440<!-- --> <!-- -->nm) and red light region (~600<!-- --> <!-- -->nm), confirming their can effective excitation by blue LED chips. Through precise control of the crystal field environment surrounding Cr³⁺ ions, the emission spectra of SLASSO: <em>x</em>Cr³⁺ phosphors demonstrate tunability from narrow-band to broadband emission, with emission peaks adjustable from 705<!-- --> <!-- -->nm to 807<!-- --> <!-- -->nm and FWHM expandable from 88<!-- --> <!-- -->nm to 185<!-- --> <!-- -->nm. SLASSO: 2%Cr³⁺ phosphor demonstrates high quantum efficiency (75%) and excellent thermal stability (95%@423<!-- --> <!-- -->K). By designing the energy transfer between Cr³⁺ and Yb³⁺, SLASSO: 2%Cr³⁺, 1%Yb³⁺ phosphors achieved both enhanced luminescence above 1000<!-- --> <!-- -->nm and zero thermal quenching (103%@423<!-- --> <!-- -->K). A prototype NIR pc-LED device demonstrated remarkable performance, achieving an output power of 59.68<!-- --> <!-- -->mW at 300<!-- --> <!-- -->mA and a high photoelectric conversion efficiency of 30.76% under 10<!-- --> <!-- -->mA. These results highlight the SrLu₂Al₃ScSiO₁₂: Cr³⁺, Yb³⁺ phosphor's potential for diverse applications, including non-destructive testing, medical diagnostics, anti-counterfeiting, and night vision technologies.","PeriodicalId":344,"journal":{"name":"Journal of Alloys and Compounds","volume":"149 1","pages":""},"PeriodicalIF":6.2,"publicationDate":"2025-05-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144137022","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Hollow ZnS microspheres loaded with WO₃ as a bidirectional catalyst for the redox of sulfur in Lithium-Sulfur batteries","authors":"Xiangzeng Meng, Panting Cao, Xingtao Qi, Shouyu Hong, Luqiao Jin, Binghui Fan, Cheng He, Yeqiang Che, Ji Yu, Ze Zhang, Zhenyu Yang, Jianxin Cai","doi":"10.1016/j.jallcom.2025.181247","DOIUrl":"https://doi.org/10.1016/j.jallcom.2025.181247","url":null,"abstract":"The slow conversion kinetics of lithium polysulfides (LiPSs) during cycling in lithium-sulfur (Li-S) batteries is a major issue hindering their development. It often results in rapid capacity decay and low sulfur utilization. In this study, a novel sulfur host was fabricated through a simple two-step hydrothermal method. First, this work prepared uniformly sized hollow ZnS microspheres via hydrothermal synthesis, and then grew sheet-like WO₃ on the dispersed ZnS microspheres via hydrothermal treatment. The ZnS microspheres enable the rapid conversion of LiPSs, while WO₃ anchors the LiPSs. Due to the surface synergistic effect of ZnS and WO₃, the sulfur host based on a heterostructure interface improves electrical conductivity and accelerates the reaction kinetics of polysulfides, thereby increasing the utilization of sulfur as the active material. The lithium-sulfur batteries based on the WO₃/ZnS sulfur host demonstrate excellent capacity retention and outstanding rate performance. S@WO₃/ZnS batteries maintain a discharge capacity of 579 mAh g⁻¹ after 300 cycles at 0.5<!-- --> <!-- -->C, with a capacity retention rate of 71.2% and a low decay rate of only 0.095% per cycle. This new sulfur host holds great potential for advancing the practical applications of Li-S batteries.","PeriodicalId":344,"journal":{"name":"Journal of Alloys and Compounds","volume":"27 1","pages":""},"PeriodicalIF":6.2,"publicationDate":"2025-05-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144145825","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Self-degradable magnesium alloy-based temporary plugging ball for fracturing in deep reservoir","authors":"Tianyu Jiang ,&nbsp;Zehang Lu ,&nbsp;Herui Fan ,&nbsp;Xiaolong Wang ,&nbsp;Lin Li ,&nbsp;Caili Dai ,&nbsp;Enyang Liu","doi":"10.1016/j.jallcom.2025.181221","DOIUrl":"10.1016/j.jallcom.2025.181221","url":null,"abstract":"<div><div>With the exploration and development of deep-buried reservoirs in China, the existing techniques are struggling to meet the demand for deep fracturing. It is of great significance to develop a new type of high-temperature and high-salinity resistant temporary plugging material for efficient transformation of the reservoir, enhancing conductivity, and increasing the cumulative oil and gas production. Metal-based temporary plugging balls (TPBs) generally have good temperature and pressure resistance, but at the same time face the challenge of long degradation time. In this research, a kind of fast degrading temporary plugging ball (FD-TPB) was prepared using the stir casting method, which can maintain high-strength mechanical properties while forming low corrosion potential and exhibiting excellent degradation performance. The experimental results show that the density of FD-TPB is 1.75 g·cm^–3, and the settling velocity in fracturing fluid is 7.01 cm·min^–1. Vickers hardness is 46.38 HV at room temperature, compressive strength could reach 180 MPa at 210℃. The simulated plugging and diverting fracturing experiments show that it can effectively carry 49.17 MPa pressure under the temperature of 180℃, complete the operation and successfully create fractures in the reformed core. FD-TPB has a self-corrosion potential of –1.70 V and a self-corrosion current density of 3.15 × 10⁻⁵ A·cm⁻². At reservoir conditions of 210℃ and 22 × 10⁴ mg·L^–1 salinity formation water, the weight loss of FD-TPB can reach 90.1 % within 100 h. The mechanism of Fe nanoparticles enhancing degradation was proposed based on the morphological changes during degradation and microstructure of the materials. The successful development of FD-TPB provides a new technical solution for the efficient exploitation of deep oil and gas resources, potentially enhancing reservoir stimulation effects, and increasing cumulative oil and gas production.</div></div>","PeriodicalId":344,"journal":{"name":"Journal of Alloys and Compounds","volume":"1033 ","pages":"Article 181221"},"PeriodicalIF":5.8,"publicationDate":"2025-05-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144136931","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Piezoelectric nanogenerators with bacterial cellulose-ZnO composites for human self-powered healthcare sensors","authors":"Meng Xiao ,&nbsp;Xiangyu Dong ,&nbsp;Zhaochen Wang ,&nbsp;Liangtian Zhang ,&nbsp;Zening Lu ,&nbsp;Boxue Du","doi":"10.1016/j.jallcom.2025.181239","DOIUrl":"10.1016/j.jallcom.2025.181239","url":null,"abstract":"<div><div>This study pioneers a high-performance, eco-friendly piezoelectric nanogenerator by integrating bacterial cellulose (BC) with zinc oxide (ZnO) nanoparticles, offering a novel pathway for next-generation self-powered medical sensors. Unlike conventional rigid generators, the BC/ZnO composite uniquely combines natural flexibility, biodegradability, and high piezoelectric responsiveness, making it ideal for conformal integration with human skin. Systematic optimization of ZnO content revealed that at 20 wt% (BZ4 membrane), the device achieved a peak output voltage of 0.12 V and a maximum piezoelectric constant of 25.6 pC/N under a 5 N load—five times greater than that of pure BC. The sensor exhibited excellent pressure sensitivity (about 0.5 V/N) and retained over 95 % of its performance after 10,000 mechanical cycles. Most notably, the self-powered sensor demonstrated real-time monitoring of human pulse and respiration with no external power, showcasing its practical viability. This work introduces an innovative, sustainable solution for flexible bioelectronic interfaces, paving the way for intelligent health monitoring and autonomous medical diagnostics.</div></div>","PeriodicalId":344,"journal":{"name":"Journal of Alloys and Compounds","volume":"1032 ","pages":"Article 181239"},"PeriodicalIF":5.8,"publicationDate":"2025-05-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144136935","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Modification of the crystallinity and electroluminescence properties of Er-doped MgGa2O4 spinel nanofilms by inserting Al2O3 nanolayers","authors":"Xinliang Guo,&nbsp;Zengxin Yan,&nbsp;Zejun Ye,&nbsp;Yang Yang,&nbsp;Jiaming Sun","doi":"10.1016/j.jallcom.2025.181230","DOIUrl":"10.1016/j.jallcom.2025.181230","url":null,"abstract":"<div><div>In pursuit of better electroluminescence (EL) performance from Er-doped MgGa_xAl_yO₄:Er (MGAO:Er) spinel nanofilms, multiple Al₂O₃ nanolayers are inserted into the Ga₂O₃/MgO/Er₂O₃ nanolaminates by atomic layer deposition. The Al₂O₃ interlayers result in a higher crystallization temperature, while the changes in lattice constant and binding energy verify the finite substitution of Ga by Al ions in spinel lattice by inserting sufficient Al₂O₃ nanolayers. The comparison confirms the difference in crystallization due to the intact Al₂O₃ nanolayers, rather than the change in inversion degree of spinel lattice, results in the different EL spectra. The EL excitation efficiency of the optimal device (4 Al₂O₃ nanolayers, 700 °C-annealed) reaches 4.5 %, with the maximum emission intensity of 14.5 mW cm⁻². The EL devices based on MGAO:Er nanofilms annealed at 600–700 °C exhibit significantly improved operation stability, the device utilizing appropriate Al₂O₃ interlayers (4 layers in a ∼80 nm film) achieves the stable operation during continuous electrical injection for more than 10 days, benefiting from the quasi-crystalline structure and smooth morphology of the MGAO:Er spinel nanofilms. This work further reveals the changes in lattice crystallinity by the regulation of component and annealing temperature of oxide nanolaminates, and contributes to the silicon-based optoelectronic application of artificially designed nanofilms.</div></div>","PeriodicalId":344,"journal":{"name":"Journal of Alloys and Compounds","volume":"1032 ","pages":"Article 181230"},"PeriodicalIF":5.8,"publicationDate":"2025-05-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144137017","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Competition between superconductivity and ferromagnetism in 2D Janus MXH (M = Ti, Zr, Hf, X = S, Se, Te) monolayer","authors":"Jakkapat Seeyangnok ,&nbsp;Udomsilp Pinsook ,&nbsp;Graeme J. Ackland","doi":"10.1016/j.jallcom.2025.180900","DOIUrl":"10.1016/j.jallcom.2025.180900","url":null,"abstract":"<div><div>Two-dimensional Janus transition-metal chalcogenide hydrides (2D-JTMCs) have generated a lot of interest as potential 2D superconductors, with numerous studies showing a transition from a metallic to a superconducting state at low temperature. They feature a three-layered structure consisting of a central transition metal layer, with chalcogen atoms below and hydrogen atoms above. The opening of a superconducting gap can stabilize a material when a metal has a high density of states at the Fermi level. Magnetic states also commonly result from a high density of states at the Fermi level in the unpolarized material (Stoner, 1938 <span><span>[1]</span></span>). In this study, we systematically investigate the instability of the normal state to superconductivity and ferromagnetism in two-dimensional hexagonal 2H and 1T Janus transition-metal chalcogenide hydrides (MXH), where <span><math><mrow><mi>M</mi><mo>=</mo><mtext>Ti, Zr, Hf</mtext></mrow></math></span> and <span><math><mrow><mi>X</mi><mo>=</mo><mtext>S, Se, Te</mtext></mrow></math></span>. In the normal metallic phase, Fermi surface instability leads to the formation of Cooper pairs, driving a superconducting phase transition characterized by a finite superconducting gap energy. We estimate the critical temperature (<span><math><msub><mrow><mi>T</mi></mrow><mrow><mi>c</mi></mrow></msub></math></span>) using the Allen–Dynes formula and compute the superconducting gap by solving the anisotropic Migdal–Eliashberg equations, predicting <span><math><msub><mrow><mi>T</mi></mrow><mrow><mi>c</mi></mrow></msub></math></span> values in the range of 10–35 K. However, most JTMCs favor ferromagnetism over the normal metallic phase, with energy differences of 10–30 meV . Even after accounting for the superconducting gap energy, ferromagnetism remains energetically preferred. Using DFT with an on-site Coulomb interaction <span><math><mi>U</mi></math></span>, we find that some JTMCs exhibit intrinsic half-metallic ferromagnetism. Our results suggest that a high electronic density of states in the normal metallic phase can drive the emergence of intrinsic half-metallic ferromagnetism, which is essential for spintronic and valleytronic applications.</div></div>","PeriodicalId":344,"journal":{"name":"Journal of Alloys and Compounds","volume":"1033 ","pages":"Article 180900"},"PeriodicalIF":5.8,"publicationDate":"2025-05-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144136936","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}