Si doping effects on the photocatalytic activity of TiO2 nanotubes film prepared by an anodization process

In order to improve the quantum efficiency of TiO2 nanotube film, Si-doped TiO2 nanotubes were prepared by anodizing Ti in HF/Na2SiF6 solution. The experimental results show that the presence of Si can separate photogenerated electrons and holes effectively. It was found that the photocurrent density of Si-doped TiO2/Ti electrode is 2–3 times higher than that of undoped TiO2/Ti electrode, and the photoelectrocatalytic degradation rate of Si-doped TiO2/Ti electrode is increased by 76.6% over that of normal TiO2/Ti electrode at an applied potential of 1.5 V.