Cobalt-Lead-Manganese oxides combined cathode catalyst for air electrode in Zinc -air battery

Bi and tri metalic oxides based on Mn, Pb and Co composite catalysts were prepared by oxidation of metal acetates with KMnO4. The structure of the catalysts was characterized by X-ray diffraction (XRD). It is found that the Mn2Pb2CoOx catalyst has amorphous structure and contains various oxides of Mn, Pb and Co. Electrocatalytic activity of catalysts in 6 M KOH was studied using Cyclic Voltammetry (CV) and polarization. Cyclic Voltammetry plot of Mn2Pb2CoOx catalyst showed higher electrocatalytic activity towards the Oxygen Reduction Reaction (ORR) compared to other tri and bimetallic composite catalysts. The kinetics of ORR on the catalysts was investigated using the rotating disk electrode technique in 6 M KOH solution. From the slope of Koutecky-Levich plots, it is evident that the ORR on Mn2Pb2CoOx is a 4-electron transfer process. With these inherent features, the zinc-air battery was fabricated using various catalysts and their performance was examined for practical applications.