Highly oriented undoped and Zn-doped titania (TiO2) nanotubes were electrochemically fabricated by one-step anodization of titanium foil in a freshly prepared aqueous solution of zinc fluoride (ZnF2) and ethylene glycol (EG). XRD and Raman spectroscopy unveiled the typical characteristic of anatase phase of TiO2 nanotube without any distinct dopant related peaks. SEM and AFM observation confirmed the formation of nanotubes and revealed that the Zn doping did not distort the tube morphology of TiO2. The doping of Zn was confirmed by energy dispersive X-ray as well as X-ray photospectroscopy. Due to one-step anodization process, instead of surface doping, the Zn2+ ions were incorporated into the bulk of TiO2 nanotubes. With increasing Zn doping in nanotubes, a gradual decrease in the band gap of TiO2 (2.84 eV) was observed. Photoluminescence measurements revealed that the doping of Zn enhanced the number of charge carriers, which eventually boosted the photocatalytic activity of TiO2 nanotubes. Compared to undoped nanotubes, the as prepared Zn-doped TiO2-nanotubes showed excellent photocatalytic activity for methylene blue degradation (reaction rate constant k = 0.19 min(-1)) under visible light irradiation. (C) 2015 Elsevier B.V. All rights reserved.