Nafion/lead oxide–manganese oxide combined catalyst for use as a highly efficient alkaline air electrode in zinc–air battery

► We report a highly efficient air-cathode for a zinc–air battery. ► The lead oxide–manganese oxide catalyst combined with Nafion is inexpensive and easily prepared. ► The catalyst shows a catalytic activity for heterogeneous chemical disproportionation of HO 2 −. In this study, we report the application of an inexpensive and easily prepared lead oxide–manganese oxide catalyst combined with Nafion (designated as Nf/PbMnO x ) as a highly efficient air-cathode for a zinc–air battery. We verify the mechanistic study of the reduction of O 2 for Nf/PbMnO x in alkaline aqueous solution using rotating ring/disk electrode voltammetry, and also an electrochemical approach using a wall-jet screen-printed ring disk electrode. The presence of Nf/PbMnO x shows great catalytic activity for the disproportionation reaction of HO 2 − to O 2 and OH − with an overall 4e − reduction of O 2 in the first reduction reaction. The 4e − reduction of O 2 was eventually achieved at the Nf/PbMnO x through evidence from the slope of Koutecky–Levich plots. With these inherent features, we then fabricated the zinc–air battery with the Nf/PbMnO x catalyst and examine the performance for a practical application with air cathodes.