Journal of Applied Electrochemistry, Vol.50, No.6, 723-731, 2020
LaCoO3-modified RuO2-TiO2/Ti electrode as an efficient electrocatalyst for oxygen evolution reaction
A RuO2-TiO2/Ti electrode modified with LaCoO3 was successfully fabricated by thermal decomposition and its electrochemical properties were evaluated by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and stability tests. In contrast with an unmodified RuO2-TiO2/Ti electrode, the LaCoO3-RuO2-TiO2/Ti electrode displays a more uniform layer with smaller microparticles. This electrode also displays higher OER performance with lower overpotential (289 mV vs. 348 mV) at a current density of 10 mA cm(-2) and lower Tafel slope (87 mV dec(-1) vs. 104 mV dec(-1)) than the unmodified RuO2-TiO2/Ti electrode. The modified LaCoO3-RuO2-TiO2/Ti electrode possesses larger current density, higher specific voltammetric charge, and lower charge transfer resistance (R-ct) than the unmodified RuO2-TiO2/Ti electrode does in a KOH solution, according to CV and EIS studies. The LaCoO3-RuO2-TiO2/Ti electrode is very stable. The results show that the modified LaCoO3-RuO2-TiO2/Ti electrode presents higher electrocatalytic activity and good stability for OER. [GRAPHICS] .