Hierarchical CuCo2S4@NiMn-layered double hydroxide core-shell hybrid arrays as electrodes for supercapacitors

Abstract

Elaborate design and synthesis of core-shell hybrid structures consisting of multiple components have been considered as the effective approach to developing electrode materials for high-performance supercapacitors. Herein, the hybrid structure consisting of CuCo2S4 core and NiMn-layered double hydroxide (NiMn-LDH) shell is hydrothermally in situ synthesized on nickel foam without organic binders as electrode materials. The resultant CuCo2S4@NiMn-LDH core-shell hybrid arrays exhibits a high specific capacitance of 2520 F g−1 at 2 A g−1, good rate capability with a long cycle lifetime. Additionally, the obtained CuCo2S4@NiMn-LDH serves as the positive electrode while the activated carbon (AC) acts as the negative electrode, which is assembled into an asymmetric supercapacitor. Impressively, the obtained asymmetric supercapacitor (CuCo2S4@NiMn-LDH//AC) delivers a high energy density of 45.8 Wh kg−1 at the power density of 1499 W kg−1. Thereby, these electrochemical performances demonstrate that as-fabricated CuCo2S4@NiMn-LDH core-shell arrays are the promising candidates as electrodes for high-performance supercapacitors.