LAUSR

Abstract Efficient catalysts made of cheap and abundant metal ions are in need to overcome the sluggish kinetics of the anodic water oxidation reaction. The development of an inexpensive catalyst with improved performance is key to produce hydrogen by the electrolytic water splitting reaction. The user friendly chemical solution deposition method was applied to prepare films with predecided mole concentrations of copper and nickel. The mixed metal oxide with equal mole ratio of Cu:Ni (1:1) achieved the maximum activity with the onset of water oxidation at overpotential of 0.40 V (1.63 V vs RHE) and achieved the current density of 1 mA/cm2 at an overpotential of 0.420 V at pH 13. The activity of this combination is attributed to the copper facilitated in-situ formation of a layered nickel oxy-hydroxide structure. The presence of both metal ions was found to be necessary indicating a synergy between Cu and Ni for the oxygen evolution reaction. The present work representing the simple synthesis process of the catalyst with the improved water oxidation activity is a promising step to develop electrodes for water electrolysis.