Electrocatalytic activity of high specific surface area perovskite-type LaNiO3 via sol-gel route for electrolytic oxygen evolution in alkaline solution

Lanthanum nickelate was synthesized by a sol-gel method at low temperature (500 degrees C) and its interfacial electrochemical and electrocatalytic properties in 1 M KOH were investigated in film form on Ni. The oxide film was obtained by painting a slurry of oxide powder and Triton X-100 and subsequent sintering at 400 degrees C. The cyclic voltammetry of the oxide electrode in 1 M KOH indicated the formation of the diffusion-controlled quasi-reversible Ni(II)-Ni(III) redox couple, prior to the onset of O-2 evolution. The oxygen evolution reaction followed approximately first order kinetics in OH- concentration. The Tafel slope was 65 mV decade(-1). The electrocatalytic activities of LaNiO3 prepared by different methods have been compared. (C) 1997 International Association for Hydrogen Energy.