Potassium-ion batteries (PIBs), as one of the alternatives to lithium-ion batteries (LIBs), have attracted considerable attention on account of the affluence and low-cost of potassium. Moreover, CoC2O4 and graphene oxide (GO) have been used very well in lithium-ion
batteries. Hence, the hybrid CoC2O4/GO was investigated as a new anode material for PIBs. The hybrid CoC2O4/GO was synthesized by a facile and cheap method combined with supersonic dispersion. Electrochemical measurements reveal that the hybrid CoC2O4/GO
delivered an excellent cycling stability of 166 mAh g−1 at 50 mA g−1 and a superior rate capability even at 1 A g−1. These results demonstrate although the cycle ability was insufficient for practical applications, transition-metal oxalates
composites can still bring new hope to the development of PIBs.