Synthesis of Mn-N-Codoped TiO_2 Photocatalyst and Its Photocatalytic Reactivity Under Visible Light Irradiation

摘要

Visible-light responsible Mn-N-codoped TiO_2 nanocrystal photocatalysts were synthesized for the first time by a simple hydrothermal synthesis method. X-ray powder diffraction (XRD) measurement indicated that all of the photocatalysts have an anatase crystallite structure and the increase of the doping concentration had less effect on the structure and particle size. Comparing to N-doped TiO_2, a shift of the absorption edge of Mn-N-codoped TiO_2 to a lower energy and a stronger absorption in the visible light region were observed. The Mn-N-codoped TiO_2 showed a higher photocatalytic reactivity than undoped TiO_2 and N-doped TiO_2 for the photodegradation of rhodamine B (RhB) under visible light irradiation. The doping concentration had an optimal value, according to the highest photocatalytic activity. This suggested that Mn and N codoping has important effects on the improvement of visible-light responsible photocatalytic activity.