Facile synthesis of NiCo2S4 nanosheets on graphitized carbon microspheres for high-performance asymmetric supercapacitors

Abstract In this work, the hybrid structure of NiCo2S4 nanosheets onto graphitized carbon microspheres (GCMS@NiCo2S4) electrode material has been rationally fabricated by using a rapid, facile, and efficient strategy, and the synergistic effect of NiCo2S4 and GCMS on the enhanced supercapacitors performance is explored. The GCMS@NiCo2S4 electrode with capacitive dominated feature exhibited a high specific capacitance (1595.1 F g −1 at 1 A g −1) and as well as excellent cyclic stability (92% retention after 5000 cycles), which were higher than these of the electrode without GCMS (i.e. pure NiCo2S4). Charge storage analysis reveals that the capacitive dominated feature of GCMS@NiCo2S4 electrode is observed. Additionally, the as-synthesized asymmetric supercapacitor by using GCMS@NiCo2S4 electrode displays a maximum specific energy of 50.2 Wh kg−1 at a specific power of 799.9 W kg−1, together with good cyclic life with 91% capacity retention over 10000 cycles at 10 A g−1. These remarkable electrochemical performances demonstrate that GCMS@NiCo2S4 has excellent potential applications in high efficient electrochemical supercapacitor.