Rational design of heterostructured core-shell Co-Zn bimetallic selenides for improved sodium-ion storage  

作　　者：Hua-Jian Liang Xiao-Tong Li Wen-Zhi Zheng Zhi-Ting Liu Wei Yang Zi-Li Liu Yu-Fei Zhang Hao-Sen Fan Sheng-Jun Lu 

机构地区：[1]College of Materials Science and Metallurgy Engineering,Guizhou University,Guiyang,550025,China [2]School of Chemistry and Chemical Engineering,Guangzhou University,Guangzhou,510006,China

出　　处：《Rare Metals》2022年第10期3381-3390,共10页稀有金属（英文版）

基　　金：financially supported by the National Natural Science Foundation of China(Nos.52101243 and 51563002);the Natural Science Foundation of Guangdong Province(Nos.2020A1515010886 and 2021A1515010078);the Scientific and Technological Plan of Guangdong Province,China(No.2019B090905007);the Science and Technology Planning Project of Guangzhou(No.202102010373)。

摘　　要：Bimetallic selenide with core-shell structure(CoSe_(2)/ZnSe/NC@ZnSe/NC)has been successfully prepared through facile carbonization and selenization processes of its core-shell metal-organic framework precursors,in which the precursor is synthesized by epitaxial growth of zinc-based zeolite imidazolate framework(ZIF-8)on the surface of cobalt-based and zinc-based zeolite imidazolate framework(ZIF-67@ZIF-8).The coreshell structure has the advantage of alleviating the volume expansion during repeated insertion and extraction of sodium ions which can effectively avoid structural collapse.Additionally,bimetallic selenides and heterostructure are effective strategies to greatly improve the rate capability of the material.Therefore,the core-shell structural CoSe2/ZnSe/NC@ZnSe/NC material can maintain the original dodecahedron structure and delivers a specific capacity of 308.6 mAh·g^(-1)at 1.0 A·g^(-1)after 300 cycles with the desirable capacity retention of 90%.With the synergistic effects of heterostructure and core-shell structure,CoSe_(2)/ZnSe/NC@ZnSe/NC exhibits better electrochemical performance than CoSe_(2)/ZnSe/NC and CoSe_(2)/NC.These prove that both core-shell structure and heterostructure have positive effects on improving the electrochemical properties of materials.

关 键 词：Co-Zn metal selenides Heterostructures Core-shell structure Sodium-ion battery(SIB) 

分 类 号：TM912[电气工程—电力电子与电力传动] TB321[一般工业技术—材料科学与工程]