Significant enhancement of the photoelectrochemical activity of TiO2 nanotubes

In the present work, we report on a facile and effective approach to significantly enhance the photocatalytic activity of TiO2 nanotubes. The TiO2 nanotubes prepared by the electrochemical oxidation of titanium in dimethyl sulfoxide (DMSO) with 2% HF were treated in a methanol solution under UV light irradiation. In comparison with the untreated TiO2 nanotubes, the treatment resulted in a dramatic increase in the donor density of the TiO2 nanotubes by approximately 3 orders of magnitude. The treated TiO2 nanotubes exhibited a 15-fold enhancement in photocurrent and a 6.8-fold increase in the photoelectrochemical degradation of 4-nitrophenol, significant for hydrogen generation and wastewater treatment. (C) 2011 Elsevier B.V. All rights reserved.