Influence of the nickel content on the electrocatalytic activity of thin nanostructured Co–Te–Ni–O films

Abstract

The influence of nickel addition in Co-Te-O catalytic films, obtained by vacuum co-evaporation of Co, Ni, and TeO2 on electrocatalytic activity toward oxygen reactions in alkaline media has been investigated. Bifunctional gas-diffusion oxygen electrodes were pre- pared by direct deposition of catalyst films on gas- diffusion membranes consisting of hydrophobized carbon blacks. The method used allows the deposition of nano- structured films consisting of intertwined nanowires with high surface area. Thus, obtained electrodes with different atomic ratio R(Co+Ni)/Te of the catalyst, fresh and thermally treated at 100 °C temperatures were electrochemically tested by means of cyclic voltammetry and steady-state voltammetry. It has been shown that the partial replacement of Co with about 30 at.% Ni leads to the increase in the film catalytic activity toward oxygen evolution reaction.