Comparative analysis of Co₉S₈/S-doped rGO composites as high-performance electrodes via facile one-step anneal fabrication for supercapacitor application

Homogeneous Co9S8 nanoparticles embedded on rGO layers were obtained using a facile one-step anneal fabrication and the synthetic material Co9S8/S-rGO served as the electrodes for supercapacitors with excellent electrochemical behavior. The low-cost synthesis process provides a convenient and fast way for the large-scale production. Meanwhile the electrochemical performance was found in a high level through the comparative analysis of the various kinds of Co9S8/S-doped rGO by regulating the ratio of GO and TTA/Co(NO3)(2) (thioacetamide and Co(NO3)(2)). The electrode based on Co9S8/rGO-1 composite exhibited the high performance with specific capacitance of 708.3 F g(-1). Moreover, the assembled asymmetric supercapacitor Co9S8/rGO-1//rGO presented excellent energy density of 41.1 Wh kg(-1) at a power density of 750 W kg(-1). The intensive performance was attributed to the synergic effects of the S-doped rGO as conductive framework and Co9S8 as the power source with high capacity. It is believed that the Co9S8/S-doped rGO composites via a facile one-step fabrication will display a great potential for supercapacitor application. (C) 2019 Elsevier B.V. All rights reserved.