LAUSR

Abstract A composite of Co3O4/holey graphene (Co3O4/HG) was prepared via a facile hydrothermal route, and was then processed into an electrode by an electrophoretic deposition process. Holey graphene (HG) wrapped Co3O4 to form a 3D skeleton network, thereby providing high electrical conductivity, and the holes in HG could further shorten the electrolyte ion diffusion pathway. Therefore, by adjusting the mass ratio of Co3O4 to HG, the Co3O4/HG composite afforded an enhanced capacitance of 2714 F g−1 (at a current density of 1 A g−1), which is 20 times higher than that of pure Co3O4. To further explore the practical applications of Co3O4/HG, a symmetric supercapacitor employing Co3O4/HG was fabricated. The supercapacitor functioned stably at potentials up to 1.2 V, with an enhanced energy density of 165 Wh kg−1 and a high power density of 0.6 kW kg−1 at 1 A g−1.