A new sight on hydrogenation of F and N-F doped {001} facets dominated anatase TiO ₂ for efficient visible light photocatalyst

Nonmetal doping such by N and F has been studied widely to enhance the visible light photoactivity of TiO ₂. Recently, hydrogenation of pure and N doped TiO ₂ is also well studied by theoretical calculations. However, little experimental evidence is known about the nature of the hydrogenation effect played on F and N-F doped anatase TiO ₂. In this study, hydrogenation of F and N-F doped {001} facets dominated anatase TiO ₂ were prepared by annealing the doped photocatalysts in the 10-bar H ₂ atmosphere. Electron paramagnetic resonance (EPR) spectra confirmed the presence of different coordinated Ti ³⁺ and oxygen vacancies located in the hydrogenated N and N-F doped TiO ₂ as a result of removing the already located N and F species. The visible-light photocatalytic activity of hydrogenated N-F doped TiO ₂ was significantly enhanced because of the formation of defect energy state belts and disorder structures. This study gives a new sight on the interaction between H and N, F species in doping TiO ₂ and developing efficient visible light photocatalyst by hydrogenation.