LAUSR

Abstract Hierarchical mesoporous CoGa2O4 microspheres were prepared via a facile solvothermal method, following by the subsequent thermal treatment. The obtained CoGa2O4 with unique microspheres, as supercapacitor electrode material, manifests a high specific capacity of 642.4 C g−1 at current density of 1 A g−1 and an excellent cycle stability with 123% capacity retention after 20,000 cycles at high current density of 20 A g−1. When tested as hybrid supercapacitor consisting of CoGa2O4 microspheres and reduced graphene oxide (rGO) as positive and negative electrode respectively delivered an excellent cycle stability (125% capacity retention after 40,000 cycles) and maximum energy density of 36.71 Wh kg−1 at a power density of 414.1 W kg−1. It is inferred that the attractive electrochemical performance of the CoGa2O4 was introduced into hybrid supercapacitor as electrode material for the first time and it will enable CoGa2O4 with new potentials as electrode material for energy storage devices.