Nitrogen Doped TiO2 Nanotube Arrays and Its Photoelectrocatalytic Properties

N-doped Titanium dioxide (TiO2) nanotube arrays were formed by electrochemical anodization, and then impregnated in 1 mol/L ammonia for 24 h before annealed at 450℃ to synthesize N doped TiO2 arrays. The samples were characterized by scanning electron microscope (SEM), X-ray Diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) to analyse its surface morphology, crystal types and the doping behavior of nitrogen. The material was used as electrode for photoelectrocatalytic degradation of hexachlorobenzen (HCB) under irradiation of simulated sunlight. The results showed that the degradation effect reached the optimality whose rate was 95% when bias potential was 1V, the concentration of Na2SO4 was 0.2 mol/L, and pH was 5.0.