Characterization and Electrocatalytic Properties of Titanium-Based Ru0.3Co0.7-xCex Mixed Oxide Electrodes for Oxygen Evolution in Alkaline Solution

Ti-supported RuO2-Co3O4-CeO2 (Ru0.3Co0.7-xCex oxide, 0 <= x <= 0.7) electrodes were prepared by sol-gel process. The phase structure, surface morphology, and microstructure of the oxide layer were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). Electrocatalytic activity and oxygen evolution reaction (OER) kinetics on these electrodes in 1.0 mol.dm(-3) KOH solution were studied by recording open-circuit potential, cyclic voltammetry, and polarisation curves. The results showed that the appropriate content of CeO2 could reduce the grain size and increase active surface area. The electrocatalytic activity shows a strong dependence on the CeO2 content in the film. Catalytic performance of mixed oxide electrodes with 40 mol %CeO2 was the best, with the greatest voltammetric charge, 86.23 mC.cm(-2), and the smallest apparent activation energy for OER at 0.60 V was 22.76 kJ.mol(-1).