Charge-Transfer Effects in Fe-Co and Fe-Co-Y Oxides for Electrocatalytic Water Oxidation Reaction

Electrocatalytic water splitting is a feasible method to store solar, wind, and water energy in the form of hydrogen fuel. However, the sluggish oxygen evolution reaction (OER) limits the energy efficiency. It is urgent to develop high-efficiency and cost-effective OER catalysts with ample active sites and excellent durability. Herein, we adopted a facile sol-gel method to synthesize a ternary amorphous iron-cobalt-yttrium oxide. The introduction of yttrium to the iron-cobalt composite oxide can improve the dispersion of iron and cobalt to provide more active sites for OER. In addition, the addition of yttrium significantly improves the charge transfer ability of iron-cobalt-yttrium oxide and enhances the OER performance with a low overpotential of 241, 263, and 214 mV at 10 mA cm^-2 on a glassy carbon electrode, Pt electrode, and Ni foam, respectively.