Abstract:TiO2 nanotubes were prepared by annealing the as-prepared samples in air at 500 ℃, and then in hydrogen atmosphere at 300 ?C. Hydrogenated TiO2 nanotube arrays were studied by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction microscopy (XRD), and X-ray photoelectron spectroscopy (XPS). Results show that hydrogen-treated TiO2 nanotube arrays areconsisted of anatase phase TiO2 nanotube walls and disordered nanophase in the surface of TiO2 nanotube walls. It is demonstrated that the presence of the Ti-OH energy states in disordered nanophase. The hydrogenated TiO2 nanotube sample yields a photocurrent density of ~4.88 mA/cm2 vs Ag/AgCl, in 1 mol/L NaOH solution under the illumination of simulated solar light (100 mW/cm2 from lamp coupled with an AM 1.5 G filter). Remarkably, a 4-fold enhanced photocurrent density for TiO2 nanotubes after hydrogen treatment was observed