Zinc-Cobalt Alloy Deposited on the Titanium Surface as Electrocatalysts for Borohydride Oxidation

Abstract

The present work is focused on the investigation of the electrochemical oxidation of BH4 – ions in an alkaline solution on a low-cost ZnCo alloy deposited on the titanium surface. The Co and ZnCo alloy coatings were deposited on the titanium surface via electrodeposition. The morphology, structure and composition of the prepared catalysts were examined by Field Emission Scanning Electron Microscopy and Energy Dispersive X-ray Spectroscopy. The activity of the fabricated catalysts was investigated towards the oxidation of BH4 – ions by means of cyclic voltammetry. It has been determined that Co/Ti and ZnCo/Ti catalyze the oxidation of H2 generated by the catalytic hydrolysis of BH4 – and direct oxidation of BH4 – ions. The H2 oxidation current densities measured on both the catalysts are rather close and reach up to 60 mA cm–2, whereas, the borohydride oxidation current densities are ~3 times higher at -0.2 V on the ZnCo/Ti catalyst than those obtained on the Co/Ti catalyst.