Microporous titanium dioxide thin films have been fabricated on titanium plates by the micro-plasma oxidation method with the electrolyte of Na3PO4+Na2B4O7. The influence of V5+ ions addition in the electrolyte on the photocatalytic activities was investigated. A kind of typical textile industry pollutant (methylene blue) was used to evaluate the photo-catalytic activity of the films. The results showed that this activity of the films had been improved by adding V5+ ions into the electrolyte solution. The removal of methylene blue reaches 90% for 60 min when V5+ ions addition concentrate is 0.3
g/L. X-ray diffraction, scanning electron microscopy and atomic force microscopy techniques were applied to characterize the modified films. Experimental results show that the improvement in activity was related to the forming of titanium dioxide
lattice distortion, which could accept more photoexcitated holes and produce more strong surface free radicals to oxidate
adsorptive molecules.