Three-dimensional polypyrrole-enhanced flower-like ZnCo2S4 nanoclusters used as advanced electrodes for supercapacitors

Abstract Confinement transition metal compounds with conducting polymer is an effectively to inhibit the volume change during the Faradic reaction. In this work, three-dimensional flower-like polypyrrole-wrapped ZnCo2S4 (ZnCo2S4@PPy) core-shell nanoclusters were successfully prepared by two-step hydrothermal and electrochemical deposition methods. The obtained ZnCo2S4@PPy composite exhibited remarkable electrochemical performance corresponding to a specific capacitance of 1486 F g−1 at 1 A g−1, which suggested its potential use as a supercapacitor electrode material. Furthermore, the asymmetric supercapacitor containing a ZnCo2S4@PPy positive electrode demonstrated a high specific energy of 33.78 Wh kg−1 at 800.05 W kg−1 and relatively long cycle life (90% capacitance retention after 5000 cycles). The excellent electrochemical performance of ZnCo2S4@PPy can be attributed to the synergistic effect of its main components and unique flower-like core-shell structure. The results reveal that the ZnCo2S4@PPy core-shell nanocluster array is a promising electrode material for future energy-storage devices.