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.

Keywords:
fuel cells; oxygen reduction and evolution; hybrid metal oxide nanocomposites