Mn-N codoped TiO2 nanotubes with enhanced photocatalytic activity: An integrated experimental and theoretical investigation

The efficient enhancement of the photocatalytic activity of TiO2 nanotubes under visible light remains a significant challenge in current research. This study, employing density functional theory, systematically investigates the impact of Mn-N co-doping on the morphology, electronic structure, and optical properties of Hydrothermal composite treatment of TiO2 nanotubes. The successful introduction of Mn-N co-doping into the nanotubes induces impurity energy levels, reducing the bandgap while enhancing absorption capability and reflectance of visible light. Mn and N are partially incorporated into the TiO2 lattice, resulting in a reduction of the bandgap from 2.98 eV to 2.81 eV. The degradation efficiency of methylene blue solution under UV light and visible light is improved by approximately 31 % and 25 %, respectively.