Ni+RuO2 co-deposited electrodes for hydrogen evolution

RuO2 particles were co-deposited with Ni onto smooth or rough Ni supports from Ni baths of different compositions, expediently named Watts, Chloride and Thiosulfate baths. Electrodeposits were characterised by means of cyclic voltammetry, X-ray diffraction, SEM and EDX. The electrocatalytic activity of the layers for H-2 evolution from alkaline solutions was determined by quasi-stationary polarisation curves. Activity increases with RuO2 in the Ni deposit up to a limiting value. Sulphur is co-deposited from thiosulfate baths, and its presence clashes with the effect of RuO2. Co-deposition from Watts baths proved the most effective. Stability tests showed that Ni + RuO2 co-deposits are stable under condition of constant as well as intermittent electrolysis. However, in the latter case stability turned out to depend on the content of RuO2 in the layer. (C) 2000 Elsevier Science Ltd. All rights reserved.