Oxygen vacancies boosting ultra-stability of mesoporous ZnO-CoO@N-doped carbon microspheres for asymmetric supercapacitors

作     者：Di Yao Fulei Wang Wu Lei Yan Hua Xifeng Xia Jinping Liu Qingli Hao 姚迪;王福蕾;雷武;华艳;夏锡锋;刘金平;郝青丽

作者机构：Key Laboratory for Soft Chemistry and Functional MaterialsMinistry of EducationSchool of Chemical EngineeringNanjing University of Science and TechnologyNanjing 210094China Chemical Engineering and Life Science and State Key Laboratory of Advanced Technology for Materials Synthesis and ProcessingWuhan University of TechnologyWuhan 430070China 

出 版 物：《Science China Materials》 (中国科学（材料科学（英文版）)

年 卷 期：2020年第63卷第10期

页      面：2013-2027页

核心收录：

学科分类：080801[工学-电机与电器] 0808[工学-电气工程] 08[工学] 0805[工学-材料科学与工程（可授工学、理学学位）] 080502[工学-材料学] 0702[理学-物理学] 

基　　金：supported by the National Natural Science Foundation of China (21576138 and 51572127) China-Israel Cooperative Program (2016YFE0129900) the Program Foundation for Science and Technology of Changzhou, China (CZ20190001) the Priority Academic Program Development of Jiangsu Higher Education Institutions the Program for Science and Technology Innovative Research Team in the Universities of Jiangsu Province, China 

主　　题：supercapacitor zinc oxide cobaltous oxide doped carbon cycling stability heterostructure 

摘      要：Long-term cycling stability of pseudocapacitive materials is pursued for high-energy ***,the mesoporous zinc-cobalt oxide heterostructure@nitrogendoped carbon(ZnO-CoO@NC)microspheres with abundant oxygen vacancies are self-assembled through a hydrothermal method combined with an annealing *** multifunctional polyvinyl pyrrolidone(PVP)is used as a structure-directing agent,the precursor of NC and the initiator of abundant oxygen vacancies in zinc-cobalt oxide *** demonstrates the generation of surface oxygen vacancies resulted from the reduction effect of conductive NC,and further confirms the weaker interaction between the metal ions and oxygen *** a result,the electrode based on ZnO-CoO@NC in 2 mol L^-1 KOH shows enhanced capacitive performance with an excellent cycle stability of 92%retention of the initial capacitance after 40,000 charge-discharge cycles at 2 A g^-1,keeping the morphology *** assembled asymmetric supercapacitor,graphene//ZnO-CoO@NC,also performs good cyclic stability with 94%capacitance retention after 10,000 cycles at 2 A g^-*** remarkable electrochemical performance of the self-assembled ZnO-CoO@NC composite is attributed to the mesoporous architecture,abundant oxygen vacancies,conductive ZnO scaffold for CoO crystals forming heterostructure of ZnO-CoO and the high conductive NC layer covering outside of the multi-metal oxide ***,the ZnO-CoO@NC holds great promise for high-performance energy storage applications.