One-Pot Hydrothermal Synthesis of Hexagonal WO3 Nanorods/Graphene Composites as High-Performance Electrodes for Supercapacitors

Tungsten oxide (WO3) as an electrode material for supercapacitors has always suffered from low capacitance and poor rate capability. In this work, a series of WO3 nanorods/graphene composites with different weight ratios of tungsten oxide nanorods (WO3 NRs) and reduced graphene oxide (rGO) are synthesized successfully through a facile one-pot electrostatic adsorptive hydrothermal method. In these composites, rGO enhances the conductivity, transporting electrons and protons to the WO3 NRs. In addition, rGO can reinforce the structure of the WO3 NRs during frequently occurring redox reactions. At a graphene weight ratio of 1wt%, the specific capacitance of the WO3 NRs/rGO composite is 343Fg(-1) at a current density of 0.2Ag(-1). Compared with pure WO3 as electrodes, the WO3 NRs/rGO composite shows excellent specific capacity, and superior rate performance and cycling stability owing to the combined action of the double layer and pseudocapacitor. This study provides a new convenient approach to promote the electrochemical performance of tungsten oxide.