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Open Journal of Microphysics 2024年第1期14卷 1-12页

作者： Phillip Wilfsen Otieno Nyawere Department of Physical and Biological Sciences Kabarak University Nakuru Kenya

An analysis of mechanical, electronic and dynamical properties of antiperovskite Ca3BO (B = Pb, Ge, Sn) in cubic phase space group Pm-3m (221) has been studied using first principle density functional theory (DFT). Ground state energy computation was done using the Projector Augmented Wave (PAW) Pseudo Potentials and the Plane Wave (PW) basis set. The Generalized Gradient Approximation (GGA) was used for the exchange correlation. The open source code QUANTUM ESPRESSO (QE) was used in this study in which plane wave basis sets are applied for the expansion of the electronic structure wave function. Thermo_pw as a post-processing code was used for the computation of mechanical properties including bulk modulus and elastic constants with their derivatives. The lattice parameters are here calculated to be 4.87 Å, 4.86 Å and 4.84 Å for Ca3BO (B = Pb, Ge, Sn) respectively which compares well with other works. This also shows that the three crystals are similar in size and in most of their properties. In addition to this, projected density of states and band structure are also computed both showing that these materials are of semi-metallic nature and are stable in cubic phase. Phonon modes at gamma are also reported.

关键词： antiperovskite Elastic Constants Generalized Gradient Approximation

Metal/antiperovskite metal nitride composites Ag/AgNNi_(3)as novel efficient electrocatalysts for hydrogen evolution reaction in alkaline media

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Journal of Materials Science & Technology 2022年第17期112卷 222-229页

作者： Lili Zhu Bingbing Yang Ziqiang Wu Changdian Li Han Li Hui Li Yanan Huang Xiaoguang Zhu Xuebin Zhu Yuping Sun Key Laboratory of Materials Physics Institute of Solid State PhysicsHFIPSChinese Academy of SciencesHefei 230031China University of Science and Technology of China Hefei 230026China High Magnetic Field Laboratory HFIPSChinese Academy of SciencesHefei 230031China Collaborative Innovation Center of Advanced Microstructures Nanjing UniversityNanjing 210093China

Searching for effective hydrogen evolution reaction(HER)electrocatalysts is crucial for water splitting.Transition metal nitrides(TMNs)are very attractive potential candidates since of high electrical conductivity,robust stability,element rich and high activity.antiperovskite metal nitrides provide chemical flexibility since two different types of transition metal elements are contained,allowing partial substitution both for A-and M-sites.Herein,we report a novel antiperovskite metal nitride Ag_(x)Ni_(1-x)NNi_(3)(0≤x≤0.80)thin film used as highly effective HER electrocatalysts.Pure phase antiperovskite nitride can be successfully obtained for Ag_(x)Ni_(1-x)NNi_(3)with x less than 0.80.The Ag_(0.76)Ni_(0.24)NNi_(3) towards HER shows an overpotential of 122 mV at 10 mA cm^(-2)in alkaline media.Furthermore,considering the role of Ag for adsorbing hydroxyl groups,chemical engineering has been carried out for designing metal/antiperovskite nitride Ag/Ag_(x)Ni_(1-x)NNi_(3)composite electrocatalysts.The 0.18 Ag/Ag_(0.80)Ni_(0.20)NNi_(3)electrocatalyst shows a mere 13 and 81 mV of overpotential to reach 1 and 10 mA cm^(-2),respectively,showing high durability in alkaline media.These results will provide a novel type of HER catalysts based on antiperovskite metal nitrides and a strategic design for metal/antiperovskite metal nitride composite electrocatalysts for HER in alkaline media.

关键词： Hydrogen evolution reaction antiperovskite Metal nitride Composite catalyst

Mn_(3)Ag_((1-x))Cu_((x))N antiperovskite thin films with ultra-low temperature coefficient of resistance

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Journal of Materials Science & Technology 2022年第4期99卷 138-147页

作者： Cecil Cherian Lukose Guillaume Zoppi Martin Birkett Faculty of Engineering and Environment Northumbria UniversityNewcastle upon Tyne NE18STUnited Kingdom

We demonstrate the first successful attempt to partially substitute Cu into the Mn_(3)AgN-antiperovskite system to form Mn_(3)Ag_((1-x))Cu_((x))N thin films with an ultra-low temperature coefficient of resistance(TCR)for fabrication of ultra-precise passive components.Films were grown by reactive magnetron sputtering on alumina and glass substrates and were found to be amorphous in nature with highly negative TCR of-233 to-351 ppm/℃in their as-grown state.Increasing Cu alloying from x=0 to 1,resulted in increased sheet resistance,a negative shift of TCR and a change of grain morphology from spherical to elongated.Post-deposition heat treatment at 300-375℃,resulted in a positive shift of TCR and an ultra-low TCR of-4.66 ppm/℃for films with x=0.6.The heat treatment induces grain growth,surface roughness and the formation of a manganese oxide upper surface layer up until temperatures of 350℃,after which surface oxidation begins to dominate.The growth rate of the surface layer is controlled by the Cu concentration and heat treatment temperature,which both play a central role in the development of these novel ultralow TCR Mn_(3)Ag_((1-x))Cu_((x))N thin film structures.

关键词： antiperovskite Thin film Sputter deposition Annealing Surface oxidation Near-zero temperature coefficient of resistance

Effects of fluorination on crystal structure and electrochemical performance of antiperovskite solid electrolytes

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Journal of Energy Chemistry 2023年第2期77卷 521-528,I0013页

作者： Lei Gao Manrong Song Ruo Zhao Songbai Han Jinlong Zhu Wei Xia Juncao Bian Liping Wang Song Gao Yonggang Wang Ruqiang Zou Yusheng Zhao School of Materials Science and Engineering Peking UniversityBeijing 100871China Guangdong Provincial Key Laboratory of Energy Materials for Electric Power Guangdong-Hong Kong-Macao Joint Laboratory for Photonic-Thermal-Electrical Energy Materials and DevicesAcademy for Advanced Interdisciplinary StudiesSouthern University of Science and TechnologyShenzhen 518055GuangdongChina Institute for Advanced Study Shenzhen UniversityShenzhen 518055GuangdongChina

The development of all-solid-state lithium batteries(ASSLBs)depends on exploiting solid-state electrolytes(SSEs)with high ionic conductivity and electrochemical stability.Fluorination is generally considered to be an effective strategy to improve the ionic conductivity and electrochemical stability of inorganic SSEs.Here,we report the partial fluorination of the chlo rine sites in an antiperovskite,by which the orthorhombic Li_(2)OHCl was transformed into cubic Li_(2)OHCl_(0.9)F_(0.1),resulting in a fourfold increase in ionic conductivity at 30℃.The ab initio molecular dynamics simulations suggest that both the crystal symmetry and the anions electronegativity influence the diffusion of Li+in the antiperovskite structure.Besides,from the perspective of experiments and calculations,it is confirmed that fluorination is a feasible method to improve the electrochemical stability of antiperovskite SSEs.The LiFePO_(4)|Li cell based on Li_(2)OHCl_(0.9)F_(0.1) is also assembled and exhibits stable cycle performance,which indicates that fluorination of antiperovskite SSEs is an effective way to produce high-performance SSEs for practical application of ASSLBs.

关键词： antiperovskite Solid-state electrolyte Fluorination Ionic conductivity

Neutron diffraction for revealing the structures and ionic transport mechanisms of antiperovskite solid electrolytes

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Chinese Journal of Structural Chemistry 2023年第5期42卷 56-64页

作者： Lei Gao Jiangyang Pan Longbang Di Jinlong Zhu Liping Wang Song Gao Ruqiang Zou Le Kang Songbai Han Yusheng Zhao School of Materials Science and Engineering Peking UniversityyBeijing100871China Academy for Advanced Interdisciplinary Studies Southern University of Science and TechnologyShenzhen518055China Department of Physics Southern University of Science and TechnologyShenzhen518055China Institute of High Energy Physics Chinese Academy of Sciences(CAS)Beijing100049China Dongguan Neutron Science Center Dongguan523803China

Solid-state electrolytes(SSEs)play the most important role in the development of cutting-edge all-solid-state bat-teries(ASSBs).The lithium(sodium)-rich antiperovskite solid conductors have been considered as the promising SSEs due to the structural tolerance for lattice manipulation and the potential to improve ionic conductivity.In particular,lithium(sodium)-rich antiperovskite SSEs are mainly composed of light elements(e.g.,Li,O,H),which are suitable for studying the structure and ionic transport mechanism through neutron diffraction techniques.This present review summarizes the progress of neutron diffraction in analyzing the structure and revealing the ionic transport mechanisms of antiperovskite SSEs.The structure-function relationships involved in ionic transport pathways,defect chemistry,anion disorder and lattice dynamics are introduced respectively.In addition,the possible future directions for the application of neutron diffraction in antiperovskite SSEs are suggested.

关键词： Solid-state electrolytes antiperovskite Neutron diffraction Structure

Pressure-dependent electronic,optical,and mechanical properties of antiperovskite X_(3)NP(X=Ca,Mg):A first-principles study

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半导体学报:英文版 2023年第10期44卷 52-60页

作者： Chunbao Feng Changhe Wu Xin Luo Tao Hu Fanchuan Chen Shichang Li Shengnan Duan Wenjie Hou Dengfeng Li Gang Tang Gang Zhang School of Science Chongqing University of Posts and TelecommunicationsChongqing 400065China Institute for Advanced Sciences Chongqing University of Posts and TelecommunicationsChongqing 400065China School of Computer Science and Technology Northwestern Polytechnical UniversityXi’an 710129China Advanced Research Institute of Multidisciplinary Science Beijing Institute of TechnologyBeijing 100081China Institute of High Performance Computing A*STAR138632Singapore

Hydrostatic pressure provides an efficient way to tune and optimize the properties of solid materials without chang-ing their composition.In this work,we investigate the electronic,optical,and mechanical properties of antiperovskite X_(3)NP(X^(2+)=Ca,Mg)upon compression by first-principles calculations.Our results reveal that the system is anisotropic,and the lat-tice constant a of X_(3)NP exhibits the fastest rate of decrease upon compression among the three directions,which is different from the typical Pnma phase of halide and chalcogenide perovskites.Meanwhile,Ca_(3)NP has higher compressibility than Mg_(3)NP due to its small bulk modulus.The electronic and optical properties of Mg_(3)NP show small fluctuations upon compression,but those of Ca_(3)NP are more sensitive to pressure due to its higher compressibility and lower unoccupied 3d orbital energy.For example,the band gap,lattice dielectric constant,and exciton binding energy of Ca_(3)NP decrease rapidly as the pressure increases.In addition,the increase in pressure significantly improves the optical absorption and theoretical conversion effi-ciency of Ca_(3)NP.Finally,the mechanical properties of X_(3)NP are also increased upon compression due to the reduction in bond length,while inducing a brittle-to-ductile transition.Our research provides theoretical guidance and insights for future experi-mental tuning of the physical properties of antiperovskite semiconductors by pressure.

关键词： antiperovskite hydrostatic pressure physical properties first-principles calculations

Mn-based antiperovskite functional materials: Review of research

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Chinese Physics B 2013年第6期22卷 19-31页

作者：童鹏王铂森孙玉平 Key Laboratory of Materials Physics Institute of Solid State PhysicsChinese Academy of Sciences High Magnetic Field Laboratory Chinese Academy of Sciences

Our recent research on the Mn-based antiperovskite functional materials AXMn3 （A： metal or semiconducting elements; X： C or N） is outlined. antiperovskite carbides （e.g., AlCMn3） show large magnetocaloric effect comparable to those of typical magnetic refrigerant materials. Enhanced giant magnetoresistance up to 70% at 50 kOe （1 Oe=79.5775 A.m-1） over a wide temperature span was obtained in Ga1-xZnxCMn3 and GaCMn3 xNix. In Cu0.3Sn0.5NMn3.2, negative thermal expansion （NTE） was achieved in a wide temperature region covering room temperature （α = -6.8 ppm/K, 150 K-40 K）. Neutron pair distribution function analysis suggests the Cu/Sn-Mn bond fluctuation is the driving force for the NTE in Cu1- xSnxNMn3. In CuN1- xCxMn3 and CuNMn3 yCoy, the temperature coefficient of resistivity （TCR） decreases monotonically from positive to negative as Co or C content increases. TCR is extremely low when the composition approaches the critical points. For example, TCR is - 1.29 ppm/K between 240 K and 320 K in CuN0.95C0 05Mn3, which is one twentieth of that in the typical low-TCR materials （- 25 ppm/K）. By studying the critical scaling behavior and X deficiency effect, some clues of localized-electron magnetism have been found against the background of electronic itinerant magnetism.

关键词： antiperovskite magnetocaloric effect giant magnetoresistance negative thermal expansion

Preparation and the physical properties of antiperovskite-type compounds Cd1_xInxNNi3（n〈x〈0.2）and Cd1-yCuyNNi3（0〈y〈0.2）

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Chinese Physics B 2012年第4期21卷 505-512页

作者：贺兵董成杨立红葛林慧慕利斌陈晓超 National Laboratory for Superconductivity Institute of PhysicsChinese Academy of SciencesBeijing 100190China Luzhou Medical College Luzhou 646000China

Two series of Cdl-xInxNNi3 （0 〈 x 〈 0.2） and Cd1_yCuyNNi3 （0 〈 y 〈 0.2） samples were prepared from CdO, In203, CuO, and nickel powders under NH3 atmosphere at 773 K. The structural and physical properties were investigated by means of X-ray powder diffraction temperature-dependent resistivity and magnetic measurements. X-ray powder diffraction results showed that the Cd1-xInxNNi3 and Cd1_yCuyNNi3 compounds have a typical antiperovskite structure, and the CdNNi3, Cd0.9In0.1NNi3, and Cd0.9Cu0.1NNia compounds show metallic temperature-dependent resistivity and exhibit a Fermi liquid behavior at low temperature. In contrast to the paramagnetism previously reported, the CdNNi3 sample exhibits very soft and weak ferromagnetism, and no superconductivity was found in the Cd1-xInxNNi3 and Cdl-yCuyNNi3 samples down to 2 K. Each sample exhibited very soft and weak ferromagnetism, and the temperature dependence of the magnetization of the Cd1-xInxNNi3 and Cd1_yCuyNNi3 samples can be well fitted to the combination of a Bloch term and a Curie-Weiss term.

关键词： nitride antiperovskite weak ferromagnetism Fermi liquid

反钙钛矿结构氮化铜纳米片实现高效电催化甲醇氧化转化为甲酸盐

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Science China Materials 2023年第5期66卷 1820-1828页

作者：赵磊孙啟焦李懋钟亚霏沈沛祺林运祥徐坤 School of Chemistry and Chemical Engineering Key Laboratory of Functional Inorganic Material Chemistry of Anhui ProvinceAnhui Province Key Laboratory of Chemistry for Inorganic/Organic Hybrid Functionalized MaterialsKey Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of EducationAnhui UniversityHefei 230601China Institutes of Physical Science and Information Technology Anhui UniversityHefei 230601China

钙钛矿氧化物具有灵活的组成和电子结构,在电催化水氧化反应中具有很大的应用潜力.然而,钙钛矿氧化物在电催化有机小分子转化中的应用研究较少,这可能是由于其导电性差,表面重构产生活性物种所需的能垒高.在本文中,我们报道了具有典型... 详细信息

钙钛矿氧化物具有灵活的组成和电子结构,在电催化水氧化反应中具有很大的应用潜力.然而,钙钛矿氧化物在电催化有机小分子转化中的应用研究较少,这可能是由于其导电性差,表面重构产生活性物种所需的能垒高.在本文中,我们报道了具有典型反钙钛矿结构的氮化铜纳米片作为甲醇选择性转化为甲酸盐的电催化剂,其形成甲酸盐的法拉第效率超过90%.原位电化学质谱和原位红外反射吸收光谱进一步证实了制备的氮化铜样品在较宽的电位范围内具有较高的甲酸盐选择性.此外,高分辨率透射电镜、X射线吸收光谱和原位拉曼光谱表明,该催化剂在电催化过程中发生表面重构形成了氧化态铜物种壳,从而提升了其整体甲醇氧化性能,而原始的氮化铜核则利于在催化剂内部的电子传递.本研究不仅为甲醇的高选择性转化提供了一种有意义的方案,而且为有机小分子的电化学转化提供了一种新型的非氧化物钙钛矿材料模型.

关键词： antiperovskite copper nitride methanol oxidation reaction formate

Synthesis and electrochemical performance of (100-x)Li7P3S11-xLi2OHBr composite solid electrolyte for all-solid-state lithium batteries

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Journal of Energy Chemistry 2020年第8期29卷 307-316,I0011页

作者： Su-Yeon Jung Rajesh Rajagopal Kwang-Sun Ryu Department of Chemistry University of UlsanDoowang-dongNam-gu 44776UlsanSouth Korea

Li7P3S11solid electrolytes with high lithium-ion conductivity are promising candidates for use in all-solidstate lithium batteries.However,this electrolyte’s poor interfacial compatibility with lithium electrodes causes unstable cyclability.In this study,in order to address this problem,(100-x)Li7P3S11-xLi2OHBr(x=0,2,5,10,20,30,40,and 50)electrolytes are prepared by a high energy ball-milling technique and heat-treatment process.The resulting(100-x)Li7P3S11-xLi2OHBr(x=2,5,10,20,30,40,and 50)electrolytes provide improved electrochemical performance with good cycling stability and a wide electrochemical window of up to 10 V(vs.Li/Li+).Moreover,these electrolytes have high ionic conductivity of 10-4–10-5S/cm at room temperature.Particularly,the 90Li7P3S11-10Li2OHBr electrolyte displays the highest conductivity of 4.4×10-4S/cm at room temperature as well as improved cyclability.Moreover,90Li7P3S11-10Li2OHBr shows decreased interfacial resistance between the solid electrolyte and cathode electrode,which was revealed by Electrochemical Impedance Spectroscopy(EIS)analysis.The initial discharge capacity of 90Li7P3S11-10Li2OHBr was found to be 135 m Ah/g when used in a In|solid electrolyte|Li(Ni0.6Co0.2Mn0.2)O2 all-solid-state lithium battery(ASSLB).Thus,we can conclude the addition of Li2OHBr into the Li7P3S11results in enhanced electrochemical properties.

关键词： All-solid-state lithium battery Solid electrolyte Solid sulfide electrolyte Li2OHBr antiperovskite