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Near-room-temperature ferromagnetic 1T Nb1−xCrxTe2 from doping-induced phase transition of 1T’ NbTe2

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Science China Materials 2025年第7期68卷 1-9页

作者： Li, Kunqi Zhou, Yuxuan Yang, Ke Han, Yutao Yuan, Yakun Tu, Xueyang Wang, Yiyang Sun, Xuzhou Bi, Hui Fang, Yuqiang Wu, Hua Huang, Fuqiang The State Key Laboratory of High-Performance Ceramics and Superfine Microstructure Shanghai Institute of Ceramics Chinese Academy of Sciences Shanghai China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of Sciences Beijing China Laboratory for Computational Physical Sciences (MOE) State Key Laboratory of Surface Physics and Department of Physics Fudan University Shanghai China College of Science University of Shanghai for Science and Technology Shanghai China State Key Lab of Metal Matrix Composites School of Materials Science and Engineering Zhangjiang Institute for Advanced Study Shanghai Jiao Tong University Shanghai China Shanghai Qi Zhi Institute Shanghai China Hefei National Laboratory Hefei China

Magnetic transition metal dichalcogenides exhibit unique spintronic properties, making them highly promising for advanced spintronic devices. It is unpreparable 1T NbTe2, rather than the stable 1T’ phase, that has been theoretically predicted to host nontrivial topology, but its thermodynamic structural instability hinders its development in spintronic applications. Heteroatom doping is effective in not only stabilizing the 1T phase but also introducing magnetism. Herein, we synthesized a series of Nb1−xCrxTe2 (x = 0, 0.1, 0.2, 1/3, 0.4) crystals and discovered the 1T Nb2/3Cr1/3Te2 phase for the first time. Observed 1T’-to-1T structural transition occurs in NbTe2 due to the Cr doping. Thermodynamically stable Nb2/3Cr1/3Te2 is confirmed to be a 1T phase from density functional theory calculations. A notable transition from diamagnetic to ferromagnetism was found in Nb1−xCrx-Te2 with the ratio of Cr increasing. The magnetism of 1T Nb2/3Cr1/3Te2 primarily originates from localized Cr 3d electrons. This crystal achieves a Curie temperature of 254 K, surpassing most Cr-based van der Waals ferromagnets. Furthermore, 1T Nb2/3Cr1/3Te2 displays metallic behavior coexisting with the Kondo effect and a robust positive magnetoresistance (32.1% at 2 K, μ0H = 9 T). This work unveils a doping-induced phase transition mechanism and provides new layered ferromagnetic materials for spintronic devices.

关键词： 1T Nb2/3Cr1/3Te2 Kondo effect near-room-temperature ferromagnetism phase transition positive magnetoresistance effect

engineering nanointerface of molybdenum-based heterostructures to boost the electrocatalytic hydrogen evolution reaction

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Journal of Energy Chemistry 2021年第7期30卷 370-376页

作者： Tong Liu Shuqing Zhou Jing Qi Kaiwen Wang Lirong Zheng Qingming Huang Tianhua Zhou Jian Zhang State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002FujianChina School of Physical Science and Technology ShanghaiTech UniversityShanghai 201210China Key Laboratory of Applied Surface and Colloid Chemistry Ministry of EducationSchool of Chemistry and Chemical EngineeringShaanxi Normal UniversityXi’an 710000ShaanxiChina Beijing Key Laboratory and Institute of Microstructure and Property of Advanced Materials Beijing University of TechnologyBeijing 100124China Beijing Synchrotron Radiation Facility(BSRF) Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China Testing Center Fuzhou UniversityFuzhou 350116FujianChina

Rational heterostructure-design in electrocatalysts represents a promising approach toward high performance in the electrocatalytic hydrogen evolution reaction(HER).In specific,optimizing the H adsorption behavior at the surface/interface of heterostructure is of key importance to improve the catalytic ***,we demonstrate the construction of a heterostructure from a well-defined oxygenbridged Co/Mo heterometallic zeolitic imidazolate framework(MOZ) as an efficient electrocatalyst for *** optimized hybrid exhibits high catalytic activity and stability in electrolytes with a wide pH *** XPS,XAS and theoretical studies reveal that the regulation of metal species can tailor the lattice of Mo_(2)C within the hybrid and induce the formation of defect sites,which could not only induce surface charge transfer between the atoms and provide an additional active site,but also affect the H adsorption behavior at the interface of a *** work provides an effective strategy to design a heterostructure with tailored active sites for energy conversion.

关键词： Electrocatalysis Metal-organic framework Water splitting Heterostructure

Texture Evolution of Ti3v2hf2.5ta2.5 Refractory Multicomponent Alloys During Cold Rolling and Annealing

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SSRN 2024年

作者： Chen, Mingtao Li, Yuqing Jiang, Wenqing Hou, Yuhan Liu, Xiaolong Zhao, Bokai Gao, Jianbo Wang, Hongliang Li, Meijuan Sun, Kai Chen, Dongfeng Zhang, Zhongwu Department of Nuclear Physics China Institute of Atomic Energy Beijing102413 China Key Laboratory of Superlight Materials and Surface Technology Ministry of Education College of Materials Science and Chemical Engineering Harbin Engineering University 145 Nantong Street Harbin150001 China Centre of Excellence for Advanced Materials Dongguan523808 China

In this paper, the texture evolution and formation mechanism of Ti3V2Hf2.5Ta2.5 refractory multicomponent alloy under various processing conditions were systematically studied using neutron diffraction combined with electron backscattering diffraction. After cold rolling with a thickness reduction of 20%, 50% and 85%, respectively, the texture intensity increases continuously with the increase in the thickness reduction. Stable deformation components of a and g fiber orientations {001}, {111}, {111} and {111} are formed in the alloy through the joint mechanism of {112} slip system activation and deformation twins. Meanwhile, the weak texture component of h fiber orientation {001} appears attributing to shear stress. After annealing under different conditions, texture intensity decreases significantly with the increases in annealing time or annealing temperature. Partial deformation texture components are remained, while new texture components such as {113} and {112} appear, as a result of recrystallization and recovery existing simultaneously, selective growth and oriented nucleation mechanisms competing with each other. More over, under the same annealing conditions, sample with larger cold rolling deformation exhibits stronger texture. © 2024, The Authors. All rights reserved.

关键词： Textures

Ph-Responsive Drug-Loaded Microspheres Based on a Tryptophan Derived Cationic Antimicrobial Agent

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SSRN 2024年

作者： Shi, Yufeng Li, Yingying Liu, Lijia Wang, Yudan Yuan, Xuan Zhang, Chunhong Lin, Feng-Huei Liu, Yawen Key Laboratory of Superlight Materials & Surface Technology Ministry of Education Institute of Advanced Marine Materials College of Materials Science and Chemical Engineering Harbin Engineering University Harbin150001 China Yantai Research Institute Harbin Engineering University Yantai264006 China Institute of Biomedical Engineering and Nanomedicine National Health Research Institutes Miaoli35053 Taiwan Department of Biomedical Engineering

Through the esterification of tryptophan with aliphatic alcohols, a collection of tryptophan-based cationic antimicrobial compounds (Trp-Zn) was achieved. The antimicrobial efficacy of the agents was systematically assessed against Gram-positive Staphylococcus aureus, Gram-negative Escherichia coli, showed significant antibacterial activity. Among the agents, L-Trp-Z12 exhibited the highest antimicrobial efficacy, achieving minimal inhibitory concentrations of merely 0.30 μg/mL against S. aureus and 0.60 μg/mL against E. coli. Moreover, based on these antimicrobial agents, a pH-responsive controlled release microsphere was designed and fabricated using sodium alginate and polyether amine as critical constituents. The composition, morphology, controllable release properties, and the intricate connections among these characteristics of the microspheres were systematically investigated. Microsphere SA/T403-2, fabricated at pH 6.8 and 30 °C alongside a distinct surface topology featuring grooves and folds, achieved an encapsulation efficiency of 91.38% and a drug loading capacity of 4.02%. Moreover, the release dynamics of L-Trp-Z12-loaded microspheres (SA/T403-L-Trp-Z12) were examined in environments mimicking gastric fluid (pH 1.2) and intestinal fluid (pH 7.4). The results showed that the cumulative release rate at pH 7.4 is twice that at pH 1.2 and the microspheres were found to have potential as drug carriers for colonic targeted drug delivery. © 2024, The Authors. All rights reserved.

关键词： Escherichia coli

Speedup of high-order unconstrained binary optimization using quantum 2 lattice gauge theory

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arXiv

arXiv 2024年

作者： Wang, Bi-Ying Cui, Xiaopeng Zeng, Qingguo Zhan, Yemin Yung, Man-Hong Shi, Yu Wilczek Quantum Center Shanghai Institute for Advanced Studies Shanghai201315 China Yangtze River Delta Industrial Innovation Center of Quantum Science and Technology Suzhou215100 China Department of Physics State Key Laboratory of Surface Physics Fudan University Shanghai200433 China Shenzhen Institute for Quantum Science and Engineering Southern University of Science and Technology Shenzhen518055 China International Quantum Academy Shenzhen518048 China Guangdong Provincial Key Laboratory of Quantum Science and Engineering Southern University of Science and Technology Shenzhen518055 China Shenzhen Key Laboratory of Quantum Science and Engineering Southern University of Science and Technology Shenzhen518055 China

An important and difficult problem in optimization is the high-order unconstrained binary optimization, which can represent many optimization problems more efficient than quadratic unconstrained binary optimization, but how to quickly solve it has remained difficult. Here we present an approach by mapping the high-order unconstrained binary optimization to quantum 2 lattice gauge theory defined on the dual graph, and propose the gauged local quantum annealing, which is the local quantum annealing protected by the gauge symmetry. We present the quantum algorithm and its corresponding quantum-inspired classical algorithm for this problem, and achieve algorithmic speedup by using gauge symmetry. By running the quantum-inspired classical algorithm, we demonstrate that the gauged local quantum annealing reduces the computational time by one order of magnitude from that of the local quantum annealing. © 2024, CC BY.

关键词： Annealing

N-Doped Porous Reduced Expanded Graphite Oxide/Multi-Component Composite With Excellent Microwave Absorbtion Performance

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SSRN 2024年

作者： Sun, Minglei Zhao, Dong Feng, Qianyi Zhou, Junyan Cui, Jiahao Liu, Zhongqing Liu, Xiubo Zhao, Shengbin School of Mechanical and Electrical Engineering Soochow University 8 Jixue Road Suzhou215021 China Suzhou Wave Vector Advanced Material Technology Co. Ltd. Suzhou215021 China Hunan Province Key Laboratory of Materials Surface/Interface Science & Technology Central South University of Forestry & Technology Changsha410004 China

Three-dimensional lightweight porous REGO (REGO-N) was prepared by hydrothermal method, and CNT and CoFe2O4 were loaded onto the surface of REGO-N. The influence of N doping content and multi-component composite on the absorption properties was systematically studied. The result shows that porous structure of REGO promotes multiple reflection of microwave and improves impedance. The doping of N atoms introduces defects and electric dipoles, effectively enhancing polarization loss. CNT, CoFe2O4, and REGO construct dense conductive networks and interface contacts, facilitating electron migration and hopping, and also generating abundant interfacial polarization loss and magnetic loss. The reflection loss (RL) of CF@CNT/REGO-3N reaches -51.71 dB at a thickness of 2 mm. The effective absorption bandwidth (RL © 2024, The Authors. All rights reserved.

关键词： Iron compounds

Two-Dimensional Hybrid Double Perovskite (Pa)2csagbibr7 Single Crystals for X-Ray Detection

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SSRN 2022年

作者： Yu, Shouwu Zhang, Xin Liu, Peirong Yang, Zhou Meng, Xianguang College of Materials Science and Engineering North China University of Science and Technology Hebei Tangshan06210 China Key Laboratory of Applied Surface and Colloid Chemistry Ministry of Education Shaanxi Key Laboratory for Advanced Energy Devices Shaanxi Engineering Lab for Advanced Energy Technology Institute for Advanced Energy Materials School of Materials Science and Engineering Shaanxi Normal University Xi’an710119 China

Due to its low toxicity and human-friendly qualities, lead-free double perovskite has emerged as a material of choice for green optoelectronic applications. In recent years, X-ray detection has been one area where double perovskite has seen very promising application potential. We have developed a larger size 2D double perovskite (PA)2CsAgBiBr7 single crystal by adding propylamine (PA). It has good X-ray response and retains the high stability of the 2D material. Under a 40 V bias voltage, the built-in planar Au/(PA)2CsAgBiBr7/Au X-ray detector exhibits a sensitivity of 317.9 μC Gy-1 cm-2. © 2022, The Authors. All rights reserved.

关键词： Perovskite

Preparation and Characterization of Wear Resistant Tio Layer on Ti Alloy

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SSRN 2023年

作者： Liu, Chenxu Gong, Yajing Wang, Yuechang Zhou, Chenchen Zhang, Jin Tian, Yu Meng, Yonggang State Key Laboratory of Tribology Tsinghua University Beijing100084 China Key Laboratory of Traffic Safety on Track of Ministry of Education School of Traffic & Transportation Engineering Central South University Changsha410075 China School of Mechanical Engineering and Automation Harbin Institute of Technology Shenzhen518055 China School of Materials Science and Engineering Nanyang Technological University Singapore639798 Singapore Beijing Key Laboratory for Corrosion Erosion and Surface Technology Institute of Advanced Materials and Technology University of Science and Technology Beijing Beijing100083 China

Titanium monoxide (TiO) is golden in color, and of good chemical inertness and high hardness, making it a potential candidate for decorative and protective coatings. In this study, a TiO layer was coated on Ti alloy substrate through a combination of cathode plasma electrolysis (CPE) and comproportionation between the Ti substrate and Ti4+ from the electrolyte. The thickness of the obtained TiO layer was around 500 nm, with a hardness of 11 GPa, a modulus of 220 GPa and a critical load of 55 N. The coefficient of friction of the CPE-treated sample vs. ZrO2 ball was decreased from 0.4~0.6 to around 0.2 when the Hertz pressure was less than 885 MPa. The wear rate of the CPE-treated sample was reduced by ~450 times compared with that of the untreated Ti alloy. Correspondingly, the wear rate of the ZrO2 ball was reduced by ~170 times. In addition, wear resistance of the CPE-treated samples was also significantly improved for common metallic materials (such as stainless steel, carbon steel, or copper alloy) as the counterpart. The surface morphology evolution and the mechanical properties of the TiO layer contribute to the excellent antiwear effects. CPE demonstrates a technologically relevant capability, especially in forming a TiO antiwear layer on Ti alloy. © 2023, The Authors. All rights reserved.

关键词： Electrolytes

Perovskite-a wonder material for solar cell applications

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Perovskite-a wonder material for solar cell applications

第九届新型太阳能材料科学与技术学术研讨会

作者： Shengzhong(Frank) Liu Dalian National Laboratory for Clean Energy Dalian Institute of Chemical PhysicsChinese Academy of Sciences Key Laboratory of Applied Surface and Colloid Chemistry Ministry of EducationShaanxi Key Laboratory for Advanced Energy Devices Shaanxi Engineering Lab for Advanced Energy Technology School of Materials Science & Engineering Shaanxi Normal University

The lead-halide-based perovskite appears to be a wonder material for photovoltaic,optoelectronic and photoelectronic applications. In only a few years, its solar cell efficiency has been increased to 25.7%, higher than all other thin film solar cells. Unfortunately, its further application is still roadblocked mainly by its large-area scalable fabrication and longterm stability. In this article, we report a large area vacuum deposition process to fabricate high-efficiency perovskite solar cells with high stability. Meanwhile,

关键词： Perovskite-a wonder material for solar cell applications