Carbon and binder free rechargeable Li-O₂ battery cathode with Pt/Co₃O₄ flake arrays as catalyst

Pt nanoparticles modified Co₃O₄ flake arrays are prepared by an electrochemically assisted method and the subsequent cool sputtering, a carbon and binder free approach. When used as the cathode catalysts of Li-O₂ batteries, these porous films supply the O ₂ transport adequate channels by the macropores surrounded by Co ₃O₄ flakes, which endow the cathodes stable two-phase interface in discharge/charge processes. The superior ability of Pt catalyzing O₂ evolution leads the batteries showing a much lower overpotential (3.2 V) in charge process compared with those using pristine Co ₃O₄ arrays as catalysts (4.0 V). The enhancement of decomposing the discharging precipitate promotes the Li-O₂ batteries' reversibility obviously, which realize more than 30 discharge/charge cycles.