Electrochemical behavior and photocatalytic performance of nitrogen-doped TiO2 nanotubes arrays powders prepared by combining anodization with solvothermal process

Nitrogen-doped TiO2 nanotubes arrays (TNAs) powders were prepared by a two-step process, which combines an anodization method with a solvothermal treatment process. Physicochemical features of the nitrogen-doped TNAs powders were characterized by X-ray diffraction analysis, scanning electron microscopy, X-ray photoelectron spectroscopy, and diffuse reflectance ultraviolet–visible spectroscopy. Electrochemical behavior and photocatalytic performance were also measured. Results indicate solvothermal treatment transforming the TNAs powder to anatase and ammonia being the nitrogen-doping source. The electrochemical properties of the TNAs show the reversible capacity of the TNAs to be good and the TNAs powders obtained after solvothermal treatment at 100 °C for 3 h to have the best photocatalytic activities among all the measured samples due to a proper crystalline.