Journal of Power Sources, Vol.431, 220-225, 2019
Laser induced oxygen-deficient TiO2/graphene hybrid for high-performance supercapacitor
Improving the electrical conductivity of TiO2 plays an essential role in electrochemical process for supercapacitor, particularly for the intrinsic electrical conductivity. Herein, we develop a novel laser irradiation strategy to modify the electrical conductivity of TiO2 and obtain the oxygen-deficient TiO2/graphene hybrid. For the oxygen-deficient TiO2/graphene hybrid, the defects (oxygen vacancies) are introduced into TiO2, whereas the graphene sheets are integrated through laser irradiation. The oxygen vacancies enhance the intrinsic electrical conductivity, and the graphene sheets facilitate the superficial electrons transfer. The oxygen-deficient TiO2/graphene hybrid shows excellent electrochemical performance by the "inside-outside" modification strategy. Symmetric supercapacitors are also fabricated with two identical oxygen-deficient TiO2/graphene electrodes and deliver a maximum energy density of 14.1 Wh kg(-1) and a maximum power density of 8.5 kW kg(-1).