Cu-Doped Co3O4 microstructure as an efficient non-noble metal electrocatalyst for methanol oxidation in a basic solution

Abstract

A rational design of non-noble metal electrocatalysts is an urgent task to lower the cost of electrocatalysts for the methanol oxidation reaction (MOR). Herein, mesoporous Cu–Co₃O₄ electrocatalysts have been prepared using a two-step reaction. The electrocatalytic activity of a series of Co₃O₄ with Cu doping at different levels, including 0, 5, 15 and 25%, on electrodes for methanol oxidation is comparatively investigated under alkaline conditions. By the virtue of a compositional and structural control, the 15% Cu-doped microstructure showed a low onset potential in methanol oxidation and a high methanol oxidation peak current density with a high mass activity (155.96 mA mg⁻¹) and area-specific activity. Moreover, 15% Cu-doped Co₃O₄ showed an excellent stability in MOR, and could be demonstrated as a kind of superior electrocatalyst towards MOR in alkaline media. This study provides a good idea to design highly efficient electrocatalysts towards MOR due to the synergistic effect of the chemical composition and porous structure.