Core-shell structured MnxCoyO4 @MoS2 composites for advanced electrodes in supercapacitors
Menghe Jiang, Ying Wang, Cuili Xiang, Yongjin Zou, Fen Xu, Lixian Sun, Dan Cai, Chua Yong Shen
Abstract
Supercapacitors are promising environmentally friendly energy storage devices owing to their high-power density, fast charge and discharge rates, long service life , wide applicable temperature range, and green environmental protection. Electrodes largely determine superconductor performance, so it is crucial to develop electrode materials with excellent performance. In this work, Mn x Co y O 4 @MoS 2 composites were obtained by coating flake MoS 2 arrays on spherical Mn x Co y O 4 using hydrothermal and heat treatment methods. At x/y = 1:2, the Mn x Co y O 4 @MoS 2 electrode material exhibited a specific capacitance of 1422 F g −1 at 1 A g −1 , which was higher than that at x/y = 1:1 and 2:1. When assembled into an aqueous asymmetric supercapacitor , the proposed electrode material provided a specific capacitance of 131 F g −1 at 1 A g −1 . The promising cycle life of the electrode material was further illustrated by the fact that capacity retention of 85% was obtained after 5000 cycles, and the device retained a specific power of 794 W kg −1 with 46.58 Wh kg −1 . The proposed electrode material design, therefore, provides new ideas to be used in the development of advanced electrodes.