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Superconductivity in chromium nitrides Pr3Cr10-xN11 with strong electron correlations

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National Science Review 2020年第1期7卷 21-26页

作者： Wei Wu Kai Liu Yanjie Li Zhenhai Yu Desheng Wu Yuting Shao Shihang Na Gang Li Ruizhen Huang Tao Xiang Jianlin Luo School of Physical Science and Technology Shanghai Tech University School of Physical Sciences University of Chinese Academy of Sciences Kavli Institute for Theoretical Sciences Songshan Lake Materials Laboratory Department of Physics and Beijing Key Laboratory of Opto-electronic Functional Materials & Micro-nano Devices Renmin University of China Beijing National Laboratory for Condensed Matter Physics and Institute of Physics Chinese Academy of Sciences

Exploration of superconductivity in Cr-based compounds has attracted considerable interest because only a few Cr-based superconductors(CrAs, ACrAsand ACrAs(A = K, Rb, Cs, Na)) have been discovered so far and they show an unconventional pairing mechanism. We report the discovery of bulk superconductivity at 5.25 K in chromium nitride in PrCrNwith a cubic lattice structure. A relatively large upper critical field of H(0) ～12.6 T is determined, which is larger than the estimated Pauli-paramagnetic pair-breaking magnetic field. The material has a large electronic specific-heat coefficient of 170 mJ Kmol—about 10 times larger than that estimated by the electronic structure calculation,which suggests that correlations between 3d electrons are very strong in PrCrN, and thus quantum fluctuations might be involved. Electronic structure calculations show that the density of states at the Fermi energy are contributed predominantly by Cr 3d electrons, implying that the superconductivity results mainly from the condensation of Cr 3d electrons. PrCrNrepresents a rare example of possible unconventional superconductivity emerging in a 3D system with strong electron correlations. Nevertheless,clarification of the specific pairing symmetry needs more investigation.

关键词： Cr-based superconductors nitrides strong electron correlations unconventional superconductivity

Plasma-Chemical Synthesis of Nanosized Powders-nitrides,Carbides,Oxides,Carbon Nanotubes and Fullerenes

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Plasma Science and Technology 2012年第11期14卷 980-995页

作者： Katerina ZAHARIEVA Gheorghi VISSOKOV Janis GRABIS Slavcho RAKOVSKY Institute of Catalysis Bulgarian Academy of Sciences Institute of Inorganic Chemistry Riga Technical University

In this article the plasma-chemical synthesis of nanosized powders （nitrides, car- bides, oxides, carbon nanotubes and fullerenes） is reviewed. Nanosized powders - nitrides, carbides, oxides, carbon nanotubes and fullerenes have been successfully produced using different techniques, technological apparatuses and conditions for their plasma-chemical synthesis.

关键词： plasma nanosized powders nitrides carbides oxides carbon nanotubes,fullerenes

Influence of 3d transition-metal substitution on the oxygen reduction reaction electrocatalysis of ternary nitrides in acid

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Nano Research 2019年第9期12卷 2307-2312页

作者： Kevin E. Fritz Yichen Yan Jin Suntivich Department of Material Science and Engineering Cornell UniversityIthacaNew York 14850USA Kavli Institute at Cornell for Nanoscale Science IthacaNew York 14850USA

The development of non-precious,acid-stable,oxygen reduction reaction(ORR)electrocatalysts can significantly aid the commercialization of proton exchange membrane fuel cells(PEMFCs).We report a survey of the ORR electrocatalysis on 3d metal substituted(M=Mn,Fe,Co)molybdenum and tungsten nitrides in acidic environments.We find that molybdate catalysts are more active than tungstates,with the specific activity depending on the chemistry of the substituted 3d metal.In both families,more electronegative 3d metals led to higher ORR activity(i.e.,Co>Fe>Mn).We attribute this result to the ability of the more electro negative 3d metal to withdraw electro ns from the Mo-or W-based active sites,effectively oxidizing the metal centers of the catalysts.Based on our observation,future nitride ORR electrocatalysts can be further optimized by oxidizing the Mo sites further by,for example,addi ng eve n more electro negative dopa nt metals or in corporati ng anion vaca ncies.

关键词： nitrides electrocatalysis fuel cells oxygen reduction

High-Temperature Thermodynamic Investigation of Nano-Dispersed nitrides Obtained in Thermal Plasma

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Plasma Science and Technology 2007年第2期9卷 174-176页

作者： M. GEORGIEVA G. VISSOKOV Iv. GRANCHAROV L. BRAKALOV Department of Technology of Inorganic Substances University of Chemical Technology andMetal|urgy 8 K. Okhridski Blvd. 1756 Sofia Bulgaria

The nitrides of transient metals have a high hardness, thermal stability, remarkable wear resistance in aggressive chemical mediums, melted metals and alloys, high corrosion resistance, and low coefficient of electric resistance. Under the conditions of low-temperature argon plasma （LTP）, thermodynamic investigations were conducted in the process of obtaining of A1N, TiN and Si3N4 in a temperature range of 1000 K to 6000 K. To investigate the thermodynamic possibility of obtaining nitrides, a computer model was used which provided the equilibrium composition of gaseous and solid phases at different temperatures. The conditions for chemical equilibrium of the system were based on the minimization of Gibbs＇ energy.

关键词： plasma-chemical treatment nitrides thermodynamic analysis

Synthesis and hydrodesulfurization of zirconium binary nitrides

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Chinese Science Bulletin 1997年第15期42卷 1274-1278页

作者： Zhang, YJ Zhao, XG Zhou, ZH Yan, WH Ying, PL Xin, Q CHINESE ACAD SCI DALIAN INST CHEM PHYSDALIAN 116023PEOPLES R CHINA

As a new material to be used widely in catalytic field, γ-Mo2N with high specific surface area(usually, SBET>100 m2·g-1 has recently aroused much attention. Its catalytic activities re-semble those of noble metals （Rh, Pd and Pt） in hydrogenation of hydrocarbon. Especially,it has some marvelous characteristics for deep hydrodesulfurization （HDS）, hydrodeni-

关键词： high surface area binary nitrides hydrodesulfurization H2-TPD.

Van der Waals epitaxy: A new way for growth of Ⅲ-nitrides

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Science China(Technological Sciences) 2020年第3期63卷 528-530页

作者： CHEN Yang JIA Yu-Ping SHI Zhi-Ming SUN Xiao-Juan LI Da-Bing State Key Laboratory of Luminescence and Applications Changchun Institute of OpticsFine Mechanics and PhysicsChinese Academy of SciencesChangchun 130033China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China

Inorganic semiconductor plays a key role for today’s technological progress [1–4]. Comparing with other organic semiconductors [5,6] and two-dimensional(2D) metal sulfides [7–10], Ⅲ-nitrides as direct bandgap semi... 详细信息

关键词： A new way for growth of Van der Waals epitaxy nitrides

Magnetic properties and Mossbauer spectroscopy of intermetallic compounds (Sm_(1-x)Pr_x)_2Fe_(17) and its nitrides

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Chinese Science Bulletin 1995年第11期40卷 953-957页

作者：曾贻伟鲁中华唐宁李新文赵如文杨伏明 Department of Physics Beijing Normal University Beijing 100875 China Institute of Physics Chinese Academy of Sciences Beijing 100080 China

Sinee Coey et al. prepared the R2Fe17Nx compounds by means of doping the nitrogenin gas-phase reaction, the magnetic properties of R2Fe17 intermetallic compounds havebeen significantly improved. This aroused wide interest of relevant scientists. Recent re-search results show that Sm2Fe17Nx has excellent intrinsic magnetic properties, but the nitridesR2Fe17Nx consisting of other rare-earth elements except Sm, have an easy-plane anisotropy.In addition, Sm is very expensive. This kind of permanent magnetic materials is

关键词： (Sm1-xPrx)2Fe17 and its nitrides X-ray diffraction for polycrystalline and aligned powder samples magnetic measurements Mossbauer spectroscopy effect on Pr substitution.

Patterned glass ceramic design for high-brightness high-color-quality laser-driven lightings

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Journal of Advanced Ceramics 2022年第6期11卷 862-873页

作者： Qiugui HUANG Hang LIN Bo WANG Shisheng LIN Pengfei WANG Ping SUI Ju XU Yao CHENG Yuansheng WANG Key Laboratory of Optoelectronic Materials Chemistry and Physics Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China College of Chemistry and Materials Science Fujian Normal UniversityFuzhou 350007China Fujian Science&Technology Innovation Laboratory for Optoelectronic Information of China Fuzhou 350108China School of Applied Physics and Materials Wuyi UniversityJiangmen 529020China

Up-to-date laser-driven lightings confront a challenge of simultaneously achieving good photometric and chromatic performances.Herein,the coupling of“patterned package design”and“phosphor wheel”was proposed and demonstrated effectively to deal with this tough issue,based on a new architecture of CaAlSiN3:Eu2+(CASN:Eu)glass ceramic film(GCF)on Y_(3)Al_(5)O_(12):Ce^(3+)(YAG:Ce)GC plate.The fabricated composite has no interface between the two functional layers and retains the admirable luminescent features from CASN:Eu and YAG:Ce for the microstructural integrity during co-sintering.The studies on laser-microcrystalline interactions reveal that the luminescence saturation is almost determined by thermal quenching for YAG:Ce,but is ascribed to thermal/intensity quenching which are equally crucial for CASN:Eu.Benefiting from the elaborate architecture design,good color chromaticity tunability was obtained,and severe photon reabsorption was reduced.Moreover,accompanied with the rotation induced increase of thermal convection to air and pulse-like excitation,the constructed lighting engine under blue laser driven shows bright white light with luminous flux(LF)higher than 1000 lm,adjustable chromaticity from cool to warm,and improved color rendering index(CRI)approaching to 70.

关键词： laser lightings glass ceramics(GCs) white light garnets nitrides

Molten Salt-Shielded Synthesis(MS^(3))of MXenes in Air

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Energy & Environmental Materials 2023年第2期6卷 159-164页

作者： Jinjin Chen Qianqian Jin Youbing Li Hui Shao Pengcheng Liu Ying Liu Pierre-Louis Taberna Qing Huang Zifeng Lin Patrice Simon College of Materials Science and Engineering Sichuan UniversityChengdu 610065China Materials Science and Engineering Research Center Guangxi University of Science and TechnologyLiuzhou 545006China Engineering Laboratory of Advanced Energy Materials Ningbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingbo 315201China Qianwan Institute of CNiTECH Zhongchuangyi RoadHangzhou Bay DistrictNingbo 315336China CIRIMAT Universit´e de ToulouseCNRSToulouse 31400France R´eseau sur le Stockage Electrochimique de l’Energie(RS2E)FR CNRS no 3459 Engineering Research Center of Alternative Energy Materials&Devices Ministry of EducationChina

MXenes are two-dimensional transition metal carbides and/or nitrides with unique physiochemical properties and have attracted extensive interest in numerous fields.However,current MXene synthesis methods are limited by hazardous synthesis conditions,high production costs,or difficulty in largescale production.Therefore,a general,safe,cost-effective,and scalable synthesis method for MXenes is crucial.Here,we report the fast synthesis of MXenes in the open air using a molten salt-shielded synthesis(MS^(3))method,which uses Lewis-acid salts as etchants and a low-melting-point eutectic salt mixture as the reaction medium and shield to prevent MXene oxidation at high temperatures.Carbide and nitride MXenes,including Ti_(3)C_(2)T_(x),Ti_(2)CT_(x),Ti_(3)CNT_(x),and Ti_(4)N_(3)T_(x),were successfully synthesized using the MS^(3) method.We also present the flexibility of the MS^(3) method by scaling the etching process to large batches of 20 and 60 g of Ti_(3)AlC_(2) MAX precursor in one pot.When used as negative electrodes,the prepared MS^(3)-MXenes delivered excellent electrochemical properties for high-rate Li-ion storage.

关键词： carbides lithium-ion storage molten salt synthesis MXene nitrides