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

In this study, we report the application of an inexpensive and easily prepared lead oxide–manganese oxide catalyst combined with Nafion (designated as Nf/PbMnOx) as a highly efficient air-cathode for a zinc–air battery. We verify the mechanistic study of the reduction of O2 for Nf/PbMnOx 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/PbMnOx shows great catalytic activity for the disproportionation reaction of HO2− to O2 and OH− with an overall 4e− reduction of O2 in the first reduction reaction. The 4e− reduction of O2 was eventually achieved at the Nf/PbMnOx through evidence from the slope of Koutecky–Levich plots. With these inherent features, we then fabricated the zinc–air battery with the Nf/PbMnOx catalyst and examine the performance for a practical application with air cathodes.

► 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 HO2−.