Photoelectrocatalytic Degradation of Methylene Blue by TiO_2 Nanotube Array Prepared by Anodic Oxidation

TiO2 nanotube array material was prepared by anodic oxidation of a pure titanium sheet. The average length and the diameter of the nanotubes were 1.8μm and 80-90nm respectively. After calcination at 400℃ for 2h,the amorphous nanotube walls converted to anatase phase without distortion and collapse. The TiO2 nanotube array material was used as photocatalyst to degrade methylene blue solution under UV light irradiation and UV light-electric field respectively. The synergetic effects of UV light and electric field on the degradation of methylene blue were investigated by changing the voltage from 0V to +3V. The highest synergetic efficiency of 124% is obtained under +1.4V. The degradation activity of the TiO2 nanotube array material used for several times decreases little,which reveals that the TiO2 nanotube array is adhered to the metal substrate stably.