An Integrated Cathode Engineered by Hierarchical Honeycomb-Like Copper-Molybdenum Sulfide Nanosheets for Hybrid Supercapacitor with Improved Energy Storage Capability

Abstract

The construction of integrated electrodes has been considered as a sensible strategy to boost the electrochemical properties of supercapacitors, which features improved electron and electrolyte ion transfer kinetics. In this work, a facile and easy-controlled synthetic methodology has been established to assemble hierarchical honeycomb-like copper-molybdenum sulfide nanosheets (Cu-Mo-S NSs) on a three dimensional (3D) porous nickel foam substrate as integrated cathodes for hybrid supercapacitors (HSCs). As expected, the Cu-Mo-S NSs deliver exceptional electrochemical properties including an areal capacity of 1.39 mAh cm-2 at 2 mA cm-2, a superb rate capability (0.86 mAh cm-2 at 20 mA cm-2), and especially, a prominent cycling lifespan with 95.3% capacity retention after 10000 cycles. Moreover, the as-obtained Cu-Mo-S NSs are used as integrated cathodes to pair with iron oxide particles encapsulated in reduced graphene oxide (Fe2O3@rGO) as anodes for assemble of Cu-Mo-S NSs//Fe2O3@rGO HSCs, which can deliver superior energy density of 79.04 Wh kg-1 and exceptional cycling stability with 94.9% capacity retention after 10000 cycles.

Keywords: Integrated cathodes, Cu-Mo-S nanosheets, hierarchical honeycomb-like nanostructure, hybrid supercapacitor, battery-type electrode materials