A novel WO3/graphene composite using poly(ionic liquid) as a linker for enhanced supercapacitive performance.

WO3 has attracted widespread attention as an important semiconductor for supercapacitors. However, applications of WO3 are limited by its poor performance regarding capacitance and conductivity. In this paper, a novel method is presented for preparing a WO3/reduced graphene oxide (RGO) composite, based on poly(ionic liquid) (PIL) as a linker. PIL enables a tight contact between WO3 and graphene to exploit the excellent electrical conductivity of graphene. Results of the morphology for the as-prepared WO3/PIL/RGO composite indicate that the WO3 nanoparticles are distributed uniformly on the surface of the RGO. The WO3/PIL/RGO electrode displays a much higher specific capacitance, 316 F g-1 at 1 A g-1, than that of the pure WO3 electrode. Furthermore, WO3/PIL/RGO also has good rate and long cycling performance for supercapacitors, making it a promising electrode material.