Metal-Organic Framework Nanosheet derived Petal-like Co3O4@CoNi2S4 Hybrid on Carbon Cloth with Enhanced Performance for Supercapacitors
Although ternary cobalt nickel sulfide is a promising electrode material for supercapacitors, its wide application is limited by relative poor electrochemical stability, low rate capacity and inefficient nanostructure. Here, we demonstrate that the electrochemical activity of cobalt nickel sulfide could be significantly improved by synergy from Co-MOF-derived Co3O4 skeleton. We design and fabricate petal-like Co3O4@CoNi2S4 nanowall arrays combined with carbon cloth as an excellent self-standing electrode for asymmetric supercapacitors. The Co3O4@CoNi2S4 electrodes exhibit a high specific capacitances of 880 C•g-1 at current density of 1 A•g-1 and an excellent rate capability of 81.3 % at 16 A•g-1. Furthermore, the assembled Co3O4@CoNi2S4//AC asymmetric supercapacitor (ASC) shows a high energy density of 51.1 Wh•kg-1 at a power density of 884.4 W•kg-1, the capacitance retention of Co3O4@CoNi2S4 is up to 86 % after 10000 cycles. It is believed that the presented work opens up a new strategy to fabricate high-performance supercapacitor electrodes.