Construction of three-dimensional all-carbon C60/graphene hybrids and their use in high performance supercapacitors

Abstract

Control of the three-dimensional (3D) pore structure of all-carbon C60/graphene hybrids was conducted by introducing C60 molecules into graphene laminates by a simple hydrothermal method to improve their performance as electrodes in supercapacitors. Results indicate that the strong π-π interaction between carbon hexagons in C60 and graphene skeletons favors the self-assembly of the 3D pore structure of the C60/graphene hybrids under hydrothermal conditions. The addition of C60 molecules gives the hybrids a hierarchical pore structure and redox-active sites, which contribute remarkably to the improved electrochemical performance. A specific capacitance of 332.3 F·g-1 at a current density of 1 A·g-1 was obtained in a 6 mol·L-1 potassium hydroxide solution for a hybrid optimized by an orthogonal experimental design method, which is 54.5% higher than that of the graphene without C60. This finding indicates that the all-carbon hybrids may be used as more competitive and promising electrodes for the fabrication of high performance supercapacitors.