Mesoporous La_0.6Ca_0.4CoO₃ perovskites with large surface areas as stable air electrodes for rechargeable Zn-air batteries

Large-capacity rechargeable batteries are becoming increasingly necessary for mobile devices, and the metal-air battery is currently the most promising for this application. Although Zn-air rechargeable batteries have a long research history, they remain far from commercialization due to their poor charge-discharge cycle life and are currently used only as primary batteries. One reason for this is the low stability of the air electrode against reversible operation. In this study, the extremely positive effects of a mesoporous nanosheet structure in La_0.6Ca_0.4CoO₃ perovskite oxide - a non-precious metal air electrode catalyst - on the cycle life of the Zn-air battery (>1000 cycles) with a high discharge potential of 1.15 V at 50 mA cm^-2 are demonstrated. The high reversibility is a result of low activity toward carbon oxidation during the charge process, which may result from the large surface area of the porous nanosheet structure and also the high stability of the perovskite phase.