High-Performance Flexible Energy Storage Devices Based on Graphene Decorated with Flower-Shaped MoS2 Heterostructures

Abstract

MoS₂, owing to its advantages of having a sheet-like structure, high electrical conductivity, and benign environmental nature, has emerged as a candidate of choice for electrodes of next-generation supercapacitors. Its widespread use is offset, however, by its low energy density and poor durability. In this study, to overcome these limitations, flower-shaped MoS₂/graphene heterostructures have been deployed as electrode materials on flexible substrates. Three-electrode measurements yielded an exceptional capacitance of 853 F g^-1 at 1.0 A g^-1, while device measurements on an asymmetric supercapacitor yielded 208 F g^-1 at 0.5 A g^-1 and long-term cyclic durability. Nearly 86.5% of the electrochemical capacitance was retained after 10,000 cycles at 0.5 A g^-1. Moreover, a remarkable energy density of 65 Wh kg^-1 at a power density of 0.33 kW kg^-1 was obtained. Our MoS₂/Gr heterostructure composites have great potential for the development of advanced energy storage devices.