Ag/AgI nanoparticles decorated WO3/TiO2 nanotubes with enhanced visible light photocatalytic activity

Abstract A composite photocatalyst, Ag/AgI nanoparticles decorated WO 3 pre-dopedTiO 2 nanotube arrays, were constructed, which showed enhanced catalytic activity induced by the visible light. The composite structure was fabricated by a three-step method, including electrochemical anodization, wet impregnation and photo-assisted reduction. The as-prepared materials were characterized by X-ray diffraction, X-ray photoelectron spectroscopy, field-emission scanning electron microscopy, transmission electron microscopy and ultraviolet-visible (UV–vis) diffuse reflectance spectroscopy. The results revealed that the absorption range of the TiO 2 nanotubes (TNTs) could be extended from ultraviolet to visible light range after the deposition of WO 3 species and Ag/AgI nanoparticles. Compared with the TNTs, WO 3 /TNTs and Ag/AgI − TNTs, the WO 3 /TNTs decorated with Ag/AgI(Ag/AgI/WO 3 @TNTs) showed much higher photocatalytic activity in the degradation of hydroquinone under visible light (λ≥420 nm) irradiation.