A High-Performance Asymmetric Supercapacitor Based on Tungsten Oxide Nanoplates and Highly Reduced Graphene Oxide Electrodes.

Tungsten oxide/graphene hybrid materials are attractive semiconductors for energy-related applications. Herein, we report an asymmetric supercapacitor (ASC, HRG//m-WO ASC), fabricated from monoclinic tungsten oxide (m-WO ) nanoplates as a negative electrode and highly reduced graphene oxide (HRG) as a positive electrode material. The supercapacitor performance of the prepared electrodes was evaluated in an aqueous electrolyte (1 m H SO ) using three- and two-electrode systems. The HRG//m-WO ASC exhibits a maximum specific capacitance of 389 F g at a current density of 0.5 A g , with an associated high energy density of 93 Wh kg at a power density of 500 W kg in a wide 1.6 V operating potential window. In addition, the HRG//m-WO ASC displays long-term cycling stability, maintaining 92 % of the original specific capacitance after 5000 galvanostatic charge-discharge cycles. The m-WO nanoplates were prepared hydrothermally while HRG was synthesized by a modified Hummers method.