Mesoporous NiCo_2O_4 nanoneedles@MnO_2 nanoparticles grown on nickel foam for electrode used in high-performance supercapacitors

作     者：Yanmei Li Jingjing Pan Jinzhu Wu Tingfeng Yi Ying Xie Yanmei Li;Jingjing Pan;Jinzhu Wu;Tingfeng Yi;Ying Xie

作者机构：School of Chemistry and Chemical Engineering Anhui University of Technology School of Resources and Materials Northeastern University at Qinhuangdao Key Laboratory of Functional Inorganic Material Chemistry Ministry of Education School of Chemistry and Materials Science Heilongjiang University 

出 版 物：《Journal of Energy Chemistry》 (能源化学（英文版）)

年 卷 期：2019年第28卷第4期

页      面：167-177页

核心收录：

学科分类：07[理学] 0702[理学-物理学] 

基　　金：financially supported by the National Natural Science Foundation of China (nos. 51774002 and 21773060) Anhui Provincial Science Fund for Excellent Young Scholars (no. gxyqZD2016066) 

主　　题：Supercapacitor First-principles calculations Electrochemical performance Synergistic effect NiCo2O4 

摘      要：Mesoporous NiCo_2O_4@MnO_2 nanoneedle arrays as electrode materials for supercapacitor grown on a conductive nickel foam were prepared by a facile hydrothermal route. The interconnected mesoporous structure of the NiCo_2O_4 nanoneedle arrays provides a large specific surface area for charge *** electrochemically active MnO_2 nanoparticles covered on the surface of NiCo_2O_4 nanoneedle result in a favorable synergistic storage effect because of charge redistribution at the NiCo_2O_4|MnO_2 interface,which reduces the interfacial polarization and facilitates ion diffusion. The initial specific capacitance of NiCo_2O_4@MnO_2(S2) is 1001 F g^(-1) at current density of 15 A g^(-1). The capacity retention of S2 is about87.4% after 4000 cycles, and the specific capacitance of S2 electrode only decreases from 1001 F g^(-1) to736 F g^(-1) even after 10,000 cycles. The first-principles calculations show that a chemical bonding between the NiCo_2O_4 and MnO_2 is not only helpful for stabilizing the composites but also leads to a charge redistribution at the interface, which may lead to a smaller interfacial polarization and thus beneficial for the interfacial capacity. The excellent electrochemical performance of NiCo_2O_4@MnO_2 composites(S2)can be ascribed to the high surface area, unique architecture, MnO_2 nanoparticle modification, reduced charge transfer resistance and stable interface between NiCo_2O_4 and MnO_2. The simple material synthesis and architectural design strategy provides new insights in opportunities to exhibit promising potential for practical application in energy storage.