Vertically-aligned graphene@Mn3O4 nanosheets for a high-performance flexible all-solid-state symmetric supercapacitor

Abstract

We have made a supercapacitor electrode based on carbon fabric, vertically aligned graphene nanosheets (VAGN) and Mn₃O₄ nanoparticles. The unique structure constructed by VAGN endows the electrode with high specific capacitance up to 670 F g⁻¹. Additionally we assembled two pieces of the electrode to make a highly flexible all-solid-state symmetric supercapacitor. This device demonstrates a high capacitance of 562 F g⁻¹, high energy density of 50 W h kg⁻¹, high power density of 64 kW kg⁻¹ and good stability after 10 000 cycles. Due to the flexibility of the carbon fabric, the device expresses an excellent flexibility without sacrificing the electrochemical performance when bended to 150 degrees. We believe that this electrode with its excellent electrochemical performances has an enormous potential in energy storage applications, especially for flexible and lightweight electronics.