Designed synthesis of 2D multilayer CuCo2S4 nanomaterials for high-performance asymmetric supercapacitors

Abstract

The development of asymmetric supercapacitors with good cycle stability and high energy density is becoming increasingly a research focus of energy storage systems. Herein, this work has reported a novel method to prepare CuCo2S4/Co-MOF (metal-organic framework) electrode materials. The electrochemical properties of materials are studied by changing the electrodeposition temperature. CuCo2S4-45, CuCo2S4/Co-MOF obtained at an electrodeposition temperature of 45 °C, has a microstructure of a multi-layer sheet-like two-dimensional ultra-thin honeycomb, which can shorten the diffusion path between ions/electrons. In addition, the specific capacitance of CuCo2S4-45 can reach 2879 F g−1 at 1 A g−1 as well as the capacity retention rate is 80.3% (2312 F g−1 at 20 A g−1). Asymmetric supercapacitor CuCo2S4-45//AC using activated carbon (AC) has excellent cycle stability (maintains 82.02% after 10,000 cycles), the energy density of 63.6 W h kg−1 at power density of 700 W kg−1. The results show that the material has great practical value.