Influence of electrochemical reduction of selfdoping on the low temperature crystallization and photocatalytic activities of TiO₂ nanotubes

Cost effectiveness and reducing the energy and time consumption are crucial factors of concern while material preparation for device fabrication is considered. Here a simple electro chemical reductive method of self-doping is proved for first time to achieve efficient ultrafast (5 s) low temperature (15 °C) crystallization of well aligned TiO₂ nanotubes (TONT). Moreover, the so prepared self-doped TONTs are demonstrated to exhibit superior photocatalytic performance over the undoped in the degradation of the organic pollutant methylene blue. The effect is correlated with the tailoring of the crystallinity and red shift in band gap on self-doping due to the introduction of Ti³⁺ ions and oxygen vacancies. (paper)