Enhanced supercapacitive performance of novel ultrathin SiC nanosheets directly by liquid phase exfoliation

Abstract

As a typical wide bandgap semiconductor material, silicon carbide (SiC) has been widely used in the field of electrical and electronic materials due to its excellent electron transport characteristics. In this paper, two-dimensional (2D) ultrathin SiC nanosheets (SiC NSs) were for the first time achieved directly through an improved cryo-mediated liquid phase exfoliation process. Then three-dimensional (3D) SiC/rGO hybrid aerogels were assembled by a facile hydrothermal treatment followed by freeze drying. The supercapacitive performance of the as-obtained 3D SiC/rGO hybrid aerogels is systematically investigated by the combined use of cyclic voltammetry (CV), galvanostatic charge-discharge (GCD) and electrochemical impedance spectroscopy (EIS). The specific energy of 53.22 Wh kg−1 at a current density of 1 A g−1 could be achieved with outstanding long-term cycling stability, demonstrating that ultrathin SiC NSs may be developed as promising electrode materials for high performance supercapacitors.