Number mismatch between cations and anions as an indicator for low lattice thermal conductivity in chalcogenides

查看全文 作　　者：Tingting [1,2,3]Deng;Tian-Ran [4]Wei;Hui [1,2]Huang;Qingfeng [1]Song;Kunpeng [4]Zhao;Pengfei [1]Qiu;Jiong [5]Yang;Lidong [1,2,3]Chen;Xun [1,4]Shi 机构地区：[1]State Key Laboratory of High Performance Ceramics and Superfine Microstructure,Shanghai Institute of Ceramics,Chinese Academy of Sciences,200050 Shanghai,China;[2]Center of Materials Science and Optoelectronics Engineering,University of Chinese Academy of Sciences,100049 Beijing,China;[3]School of Physical Science and Technology,ShanghaiTech University,201210 Shanghai,China;[4]State Key Laboratory of Metal Matrix Composites,School of Materials Science and Engineering,Shanghai Jiao Tong University,200240 Shanghai,China;[5]Materials Genome Institute,Shanghai University,200444 Shanghai,China 出　　处：《npj Computational Materials》索引2020年第1期,共7页 基　　金：This work is supported by the National Key Research and Development Program of China(2018YFB0703600);the National Natural Science Foundation of China(51625205,91963208,and 51802333);the Key Research Program of Chinese Academy of Sciences(KFZD-SW-421);the Youth Innovation Promotion Association of CAS(2016232). 摘　　要：Thermal conductivity is one of the most fundamental properties of materials with the value being determined by nearly all-scale structural features and multiple physical processes.Rapidly judging material’s thermal conductivity is extremely important but challenging for the applications.The material genome paradigm offers a revolutionary way to efficiently screen and discover materials with designed properties by using accessible indicators.But such a performance indicator for thermal conductivity is quite difficult to propose due to the existence of multiple mechanisms and processes,especially for the materials with complex structures such as chalcogenides.In this study,the number mismatch between cations and anions is proposed as a practical performance indicator for lattice thermal conductivity in complex copper and silver chalcogenides,which can be used to explain the observed experimental data and find new low thermal conductivity materials.Such a number mismatch brings about rich phenomena to affect thermal conductivity including the complication of the unit cell and the creation of chemical hierarchy,point defects,rattling modes and lone-pair electrons.It is expected that this rich-connotation performance indicator can be also extended to other complex materials to discover designed thermal conductivities. 关 键 词：CONDUCTIVITY thermal MISMATCH