Manganese Oxide Catalyst Grown on Carbon Paper as an Air Cathode for High‐Performance Rechargeable Zinc–Air Batteries

Abstract Manganese oxide is grown directly on carbon paper through a simple immersion process, and used as a catalyst‐modified air cathode for rechargeable zinc–air batteries. The manganese oxide is distributed evenly within the porous carbon paper, which promotes a rapid three‐phase reaction and high utilization of the active materials. Zinc–air batteries with the manganese oxide catalyst directly grown on the carbon paper exhibit improved performance compared with zinc–air batteries fabricated by using manganese oxide powder catalyst coated on carbon paper. The directly grown catalyst reduces the contact resistance and enhances the discharge/charge profile of the zinc–air batteries. Zinc–air batteries with the directly grown catalyst show a discharge voltage of 1.2 V at a current density of 15 mA cm −2 and deliver a power density as high as 108 mW cm −2 at an applied current of 168 mA cm −2 . Furthermore, good cycling stability for up to 500 cycles is achievable during continuous discharge–charge tests without the need to replace the zinc anode or replenish the electrolyte; this outperforms most currently available bifunctional catalysts for rechargeable zinc–air batteries. This study illustrates a promising platform to enhance the cycle life of rechargeable metal–air batteries.