Boosted Photoactivity of Titania Nanotube Layers Doped with a Suspension of Gold Nanoparticles

Abstract

In the present work, we report on the behavior of synthesized gold nano-particles suspension, incorporated in titanium dioxide nanotube layers (TiO2- NT) and fabricated by electrochemical anodization in 0.4 wt% hydrofluoric acid solution and we study its photocatalytic response. Gold nanoparticles were characterized using Transmission electron microscopy and X-ray diffraction. Scanning electron microscopy was used to study the morphology of TiO2 nanotube layers doped by gold nanoparticles. Boosted photocatalytic performances on the degradation of an azo dye were obtained by using TiO2 nanotube layers doped by gold nanoparticles (Au/TiO2-NT), compared to undoped TiO2 nanotube layer (TiO2-NT) catalysts. Under UV irradiation, this new nanomaterial, with noble metal-semi conductor heterojunction (Au/ TiO2-NT) exhibits a synergetic effect in accelerating the electron transfert, resulting in an enhanced photoactivity recorded in the kinetics of degradation of Acid Orange 7 (AO7). Chronoamperometry was used to highlight higher photocurrent produced by gold-titania interface submited to UV irradiation.