Graphene and Metal Oxide Composites for Supercapacitors

Graphene-metal oxide composites as supercapacitor electrodes combine the large pseudocapacitance of metal oxides with the fascinating electrical and mechanical properties and large surface area of graphene. The synthetic methods for composites are reviewed, including in-siu synthesis, solution mixing, hydrothermal method, microware irradiation and electrochemical deposition. Among these techniques, the hydrothermal method offers an effective and simple way to anchor metal oxides on the 2D graphene sheet uniformly. Consequently, the composites exhibit high capacity, high rate capability and well reversibility, presenting promising prospects as supercapacitor electrode material.