Preparation and electrocatalytic activity of gold nanoparticle embedded in highly ordered TiO 2 nanotube array electrode for electro-oxidation of galactose

Abstract

Gold nanoparticle–TiO₂ nanotube electrodes with high surface area have been successfully prepared using a two step process consisting of galvanic deposition of gold nanoparticles on TiO₂ nanotubes/Ti electrodes as support. TiO₂ nanotubes/Ti electrodes are fabricated by anodising titanium foil in a dimethyl sulphoxide fluoride containing electrolyte. Scanning electron microscopy and energy dispersive X-ray spectroscopy results indicate that the TiO₂ nanotube layers consist of individual tubes of about 60–90 nm diameters, and gold nanoparticles with a size range of 30–40 nm are well dispersed on the surface of the TiO₂ nanotube support. The electrocatalytic properties of gold nanoparticle–TiO₂ nanotube electrodes towards the electro-oxidation of galactose are investigated by cyclic voltammetry. Compared with pure gold electrodes, gold nanoparticles–TiO₂ nanotube electrodes show much higher electrochemical activity. This novel electrode can be used repeatedly and exhibits stable electrocatalytic activity for galactose oxidation.