Electrochemical capacitance performance of Fe-doped Co3O4/graphene nanocomposite: investigation on the effect of iron

Fe-doped Co3O4/graphene nanocomposite is prepared by a facile hydrothermal route and employed in electrode material of pseudocapacitor. The relevant Fe3+ ions are successfully introduced into Co3O4 lattice. The incorporation of Fe3+ ions leads to lattice distortion of Co3O4 and has synergistic effect on the morphology of Co3O4 crystal. In particular, Fe3+ ions doped Co3O4 nanosized particles (∼ 12 nm in sized) with almost no agglomeration are more uniformly deposited on the surface of graphene nanosheets, contrasting with pure Co3O4, which confirms the influence of Fe dopant substitution on the corresponding crystal surface nature. Evaluated by electrochemical measurements, as the Fe doping concentration increasing up to 1:10, the specific capacitance value of the Fe-doped Co3O4/graphene nanocomposite reaches a value of 671 Fg−1 at a current density of 5 Ag−1, and the capacitance retains at 98.7% after 1000 cycles. The fact that the improved performances compared to pure Co3O4 and Co3O4/graphene nanocomposite are demonstrated with a high specific capacitance, cycle stability and rate capability. Appropriate Fe3+ ions incorporated into the Co3O4 framework are highly beneficial for the stabilizing the lattice structure and then improves capacitance performance.

234