Nickel based metal oxide catalysts for electrochemical alkaline water splitting

Abstract

In this work the redox, the electrocatalytic and mechanistic properties for the oxygen evolution reaction (OER) of three classes of nickel based oxide electrodes were examined. The oxide materials studied were hydrous nickel oxide, electroprecipitated nickel hydroxide electrodes and thermally prepared NiO/RuO2. The characteristic structural and physical properties of the oxide materials were found to be highly influenced by the manner in which they are prepared. It was the aim here to highlight some unifying concepts of nickel based oxide materials, regardless of their preparation method. In addition, the electrocatalytic properties of nickel based oxides have been described for potential use in the industrially and commercially significant oxygen evolution reaction; the rate determining step for hydrogen production via alkaline water electrolysis. An ageing procedure, originally developed for 'battery type' electroprecipitated nickel hydroxide, was modified for a more novel hydrous nickel oxide electrode which was shown to significantly enhance catalytic activity towards the OER for the latter material.