Metal Oxide/Gold Hybrid Nanocomposites as Electrocatalysts for Alkaline Air Electrodes

MnCo2O4/Au was investigated as an electrocatalyst for the oxygen reduction and evolution in alkaline media. Polarization curves showed an unprecedented activity for the oxygen reduction due to a synergistic effect between MnCo2O4 and Au, involving Co-II/Co-III-Mn-III/Mn-IV, as revealed by in situ X-ray absorption near edge structure (XANES). Additionally, results showed favorable interaction between the oxide and Au, which enhanced the activity for the oxygen evolution reaction.