Substantially boosted photocatalytic detoxification activity of TiO2 benefited from Eu doping.

The wide energy band and high recombination rate of photogenerated carriers severely limit the photocatalytic activity of TiO2. It has been demonstrated that ion doping can induce lattice defects, change the energy band structure, optimize the separation efficiency of photogenerated carrier, thus promoting the photocatalytic activity of the catalyst. In this work, Eu-doped TiO2 was synthesized by a sol-gel method, and the composition and photogenerated carrier separation efficiency of the samples were analyzed by various characterization methods. The results show that Eu-TiO2 was successfully prepared and Eu-TiO2 exhibits higher photogenerated carrier separation efficiency and generates more superoxide radicals compared to the bare TiO2. Photocatalytic activity of the samples was evaluated by degradation of Rhodamine B (RhB), and the results show that Eu doping improves the photocatalytic activity of the samples, the sample with Eu/Ti molar ratio of 0.2% displays 2.3-fold increase in photocatalytic activity compared to the blank TiO2. The improved photocatalytic activity can be attributed to the fact that Eu doping facilitates the effective separation of photogenerated carriers.