Mesoporous Co3O4 as an electrocatalyst for water oxidation

Mesoporous Co3O4 has been prepared using porous silica as a hard template via a nanocasting route and its electrocatalytic properties were investigated as an oxygen evolution catalyst for the electrolysis of water. The ordered mesostructured Co3O4 shows dramatically increased catalytic activity compared to that of bulk Co3O4. Enhanced catalytic activity was achieved with high porosity and surface area, and the water oxidation overpotential (η) of the ordered mesoporous Co3O4 decreases significantly as the surface area increases. The mesoporous Co3O4 also shows excellent structural stability in alkaline media. After 100 min under 0.8 V (versus Ag/AgCl) applied bias, the sample maintains the ordered mesoporous structure with little deactivation of the catalytic properties.