Layered metal carbo–selenide Nb2CSe2 with van der Waals interlayer coupling  

作　　者：Junchao Wang Renfei Cheng Tao Hu Xinyue Tang Yan Liang Min Tian Ting Xiong Qiuhong Lu Qi Zhu Zhiqing Yang Xiaohui Wang Yanchun Zhou 

机构地区：[1]Shenyang National Laboratory for Materials Science,Institute of Metal Research,Chinese Academy of Sciences,Shenyang 110016,China [2]School of Materials Science and Engineering,University of Science and Technology of China,Shenyang 110016,China [3]Institute of Materials Science and Devices,School of Materials Science and Engineering,Suzhou University of Science and Technology,Suzhou 215009,China [4]School of Materials Science and Engineering,Shenyang Ligong University,Shenyang 110159,China [5]Ji Hua Laboratory,Foshan 528000,China [6]Key Laboratory for Anisotropy and Texture of Materials(Ministry of Education),School of Materials Science and Engineering,Northeastern University,Shenyang 110819,China [7]School of Materials Science and Engineering,Zhengzhou University,Zhengzhou 450001,China

出　　处：《Journal of Advanced Ceramics》2025年第1期101-110,共10页先进陶瓷(英文)

基　　金：supported by the Shenyang National Laboratory for Materials Science,Institute of Metal Research,Chinese Academy of Sciences,Basic and Applied Basic Research Program of Guangdong Province(No.2021B0301030003);Ji Hua Laboratory(No.X210141TL210)。

摘　　要：The stacking structure of Nb,CSe2,a newly synthesized layered metal carbo-selenide,was elucidated by scanning transmission electron microscopy.Nb,CSe2 features Se-Nb-C-Nb-Se quintuple atomic layers.These layers are stacked in Bernal mode.In this mode,Nb,CSe2 crystallizes in a trigonal symmetry(space group P3m1,No.164),with lattice parameters of a=3.33 A and c=18.20 A.Electronic structure calculations indicate that the metal carbo-selenide has Fermi energy crossing the bands where it touches to give a zero gap,indicating that it is an electronic conductor.As evidenced experimentally,the electrical conductivity is as high as 6.6x105 S.m-,outperforming the counterparts in the MXene family.Owing to the layered structure,the bonding in Nb,CSe2 with an ionic formula of(Nb1.48+),(C1.74-)(Se0.61-)2 is highly anisotropic,with metallic-covalent-ionic bonding in intralayers and weak bonding between interlayers.The layered nature is further evidenced by elastic properties,interlayer energy,and friction coefficient determination.These characteristics indicate that Nb,CSe2 is an analog of molybdenum disulfide(MoS2),which is a typical binary van der Waals(vdw)solid.Moreover,vibrational properties are reported,which may offer an optical identification standardfor new ternaryvdW solids in spectroscopic studies,including Raman scatteringand infraredabsorption.

关 键 词：MXene Nb2CSe2 crystal structure electronic structure elastic properties interlayer coupling Raman spectroscopy friction coefficient 

分 类 号：TG1[金属学及工艺—金属学]