Pd插层NbSe2化合物的制备、晶体结构和电学性质研究  

Synthesis, Crystal Structure, and Electrical Conductivity of Pd-intercalated NbSe2

作　　者：黄冲 赵伟[1] 王东[1] 卜克军 王思顺 黄富强[1,3] HUANG Chong;ZHAO Wei;WANG Dong;BU Kejun;WANG Sishun;HUANG Fuqiang(State Key Laboratory of High Performance Ceramics and Superfine Microstructure,Shanghai Institute of Ceramics,Chinese Academy of Sciences,Shanghai 200050,China;University of Chinese Academy of Sciences,Beijing 100049,China;State Key Laboratory of Rare Earth Materials Chemistry and Applications and Beijing National Laboratory for Molecular Sciences,College of Chemistry and Molecular Engineering,Peking University,Beijing 100871,China)

机构地区：[1]中国科学院上海硅酸盐研究所,高性能陶瓷和超微结构国家重点实验室,上海200050 [2]中国科学院大学,北京100049 [3]北京大学化学与分子工程学院,北京分子科学国家实验室,稀土材料化学及应用国家重点实验室,北京100871

出　　处：《无机材料学报》2020年第4期505-510,I0002,I0003,共8页Journal of Inorganic Materials

基　　金：National Key Research and Development Program (2016YFB0901600);Science and Technology Commission of Shanghai (16JC1401700,16ZR1440500);National Natural Science Foundation of China (Y93GJ11101);The Key Research Program of Chinese Academy of Sciences (QYZDJ-SSW-JSC013,KGZD-EW-T06);CAS Center for Excellence in Superconducting Electronics;Youth Innovation Promotion Association CAS.

摘　　要：通过固相反应法合成一系列插层化合物PdxNbSe2 (x=0~0.17)。它们与2H-NbSe2相同,属于六方晶格,空间群为P63/mmc。Pd占据NbSe2层间的八面体空位。随着Pd含量的增加,晶格常数c线性增大,而a几乎不变。X射线单晶衍射结果表明,Pd0.17NbSe2的晶格常数为a=b=0.34611(2)nm,c=1.27004(11)nm。每个Pd原子与六个Se原子键合形成[PdSe6]八面体来连接相邻的Nb-Se层,使晶体结构变得更加稳定,从而提高化合物的热稳定性。电学测试表明,随着Pd含量的增加, PdxNbSe2的剩余电阻比减小。此外,超导转变温度也随着Pd含量的增加而下降,说明Pd的引入不利于NbSe2的超导态。New intercalated compounds PdxNbSe2(x=0-0.17) were synthesized via solid-state reaction. They possess the parent structure of 2H-NbSe2 and crystalize in the hexagonal space group of P63/mmc. The intercalated Pd occupies the octahedral position in the van der Waals gaps of 2 H-NbSe2. Unit cell parameter c increases linearly with the Pd content, while a is nearly unchanged. The lattice parameter of Pd0.17NbSe2(a=b=0.34611(2) nm, c= 1.27004(11) nm) is identified by single crystal X-ray diffraction. The intercalated Pd stabilizes the crystal structure of NbSe2 by connecting the adjacent Nb-Se layers with [PdSe6] octahedra and leads to the enhanced thermostability in air. Temperature dependence of electric resistivity reveals that the residual resistivity ratio of PdxNbSe2 monotonically decreases with addition of the intercalated Pd content. The decreased superconducting critical temperature of PdxNbSe2 indicates the suppression effect of Pd intercalation on the superconductivity in the host NbSe2.

关 键 词：PdxNbSe2 过渡金属硫族化合物 晶体结构 超导 

分 类 号：O782[理学—晶体学]