Investigation of oxygen evolution on LaNi1-xMxO3 (M = Fe, Co, Cu; 0 < x < 0.5) films of controlled roughness

Real current densities for the oxygen evolution reaction (OER) have been es timated taking into account the surface roughness in the case of films of p erovskites LaNi1-xMxO3 (M = Fe, Co, Cu, 0 < x < 0.5). The oxides have been prepared in powder form via the malic acid route, involving decomposition a t 650 degrees C of an amorphous malate gel. The films were characterized ex -sity by XRD and EDAX, and in-situ by AC impedance and cyclic voltammetry ( CV). Electrocatalytic properties towards the OER were investigated by ordin ary stationnary voltammetry. It was found that AC impedence and CV yielded similar roughness factors. The substitution of Fe, Co and Cu had practicall y no effect on the roughness, current densities and reaction mechanism of t he OER, and only marginal effect on the electrocatalytic activity.