Electrocatalytic performance of CuO/graphene nanocomposites for Li–O₂ batteries

A hybrid catalyst system of a porous CuO nanowire/leaf mixture anchored onto graphene (p-CuO/G hybrid) was prepared as an oxygen-electrode electrocatalyst for lithium–oxygen (Li–O₂) batteries. The p-CuO/G hybrid was prepared via the hybridization of a porous 1D/2D CuO mixture with 2D graphene. As an oxygen-electrode electrocatalyst for Li–O₂ cells, the p-CuO/G hybrid exhibited high reversibility with a low voltage gap compared with a graphene electrode during 120 discharge–charge cycles under a fixed capacity regime of 1000 mA h g⁻¹. We demonstrated the oxygen reduction and evolution kinetics of the p-CuO/G hybrid using electrochemical impedance spectroscopy.