Graphene-based 3D composite hydrogel by anchoring Co3O4 nanoparticles with enhanced electrochemical properties.

Three-dimensional (3D) graphene-based composite materials have attracted increasing attention, owing to their specific surface area, high conductivity and electronic interactions. Here, we report a convenient route to fabricate a 3D Co₃O₄/Graphene Hydrogel (CGH) composite as an electrode material for supercapacitors. Utilizing the gelation of a graphene oxide dispersion enables the anchoring of Co₃O₄ nanoparticles on the graphene sheet surfaces and formation of the hydrogel simultaneously. Remarkably, the spherical Co₃O₄ particles can serve as spacers to keep the neighboring graphene sheets separated. The CGH exhibits a high specific capacitance (C_s) of 757.5 F g⁻¹ at a current density of 0.5 A g⁻¹, indicating its potential application as an electrode material for supercapacitors. [ABSTRACT FROM AUTHOR]