Defect Engineering of a Mott‐Schottky‐Type Self‐Supporting Electrode for Rechargeable Zinc‐Air Battery

Abstract

Developing bi-functional electrocatalysts for zinc-air batteries is still challenging due to the slow kinetics of the cathode reaction. In this work, we report a low-temperature plasma strategy to prepare Mott-Schottky-type electrodes which contain metal alloy and metal oxide. The as-obtained freestanding electrodes (Co 0.72 Fe 0.28 @CoO/CP and Ni 3 Fe@NiFe 2 O 4 / CP) exhibit remarkable electrochemical performance for oxygen reduction reaction (ORR) and oxygen evolution reaction (OER). After introducing the precious metal Pt, the ORR activity of these electrodes has improved, and the corresponding zinc-air batteries show good charge-discharge efficiency and stability. This outstanding electrochemical performance could attribute to the Mott-Schottky synergistic effects between metal alloy and metal oxide in heterojunction, high conductivity of carbon paper, and interface defects made by Plasma treatment, thus improving the intrinsic electrocatalytic activity of the oxygen reaction.