UV-light aided photoelectrochemical synthesis of Au/TiO2 NTs for photoelectrocatalytic degradation of HPAM

Abstract

TiO₂ nanotube arrays (TiO₂ NTs) loaded with Au nanoparticles were fabricated as an electrode for enhanced photoelectrocatalytic activity toward partially hydrolyzed polyacrylamide (HPAM) degradation. The honeycombed TiO₂ NTs were prepared by a two-step anodization method and modified by Au nanoparticles via an UV-light aided photoelectrochemical process. The photoelectrocatalytic (PEC) activities of TiO₂ NTs and Au/TiO₂ NTs were characterized by decomposition of HPAM. The results showed that Au/TiO₂ NTs exhibit much higher PEC activity than that of pristine TiO₂ NTs. The size and amount of Au nanoparticles can be well controlled by adjusting the concentrations of metal ion precursor in the photoelectrochemical process. Structures, element components and morphologies of TiO₂ NTs and Au/TiO₂ NTs were measured by XRD, XPS, EDS and FESEM. Photoresponse of the as prepared samples were evaluated by UV-vis DRS. The UV-light aided photoelectrochemical synthesis of Au/TiO₂ NTs contributes to the rational design of the plasmonic photocatalytic composite material based on wide band gap metal oxides for photoelectrochemical applications on degradation of polymers. As a consequence, an optimum loading amount of Au were obtained with weight percentage of 1.24 wt%.