Solar photocatalysts from Gd-La codoped TiO_2 nanoparticles

摘要

Gd-La codoped TiO_2 nanoparticles with diameter of 10 nm were successfully synthesized via a sol- gel method. The photocatalytic activity of the Gd-La codoped TiO_2 nanoparticles evaluated by photodegrading methyl orange has been significantly enhanced compared to that of undoped or Gd or La monodoped TiO_2. Ti~(4+) may substitute for La~(3+) and Gd~(3+) in the lattices of rare earth oxides to create abundant oxygen vacancies and surface defects for electron trapping and dye adsorption, accelerating the separation of photogenerated electron-hole pairs and methyl orange photodegradation. The formation of an excitation energy level below the conduction band of TiO_2 from the binding of electrons and oxygen vacancies decreases the excitation energy of Gd-La codoped TiO_2, resulting in versatile solar photocatalysts. The results suggest that Gd-La codoped TiO_2 nanoparticles are promising for future solar photocatalysts.