Synergistic Effect of Y Doping and Reduction of TiO on the Improvement of Photocatalytic Performance.

Pure TiO and 3% Y-doped TiO (3% Y-TiO) were prepared by a one-step hydrothermal method. Reduced TiO (TiO-H) and 3% Y-TiO (3% Y-TiO-H) were obtained through the thermal conversion treatment of Ar-H atmosphere at 500 °C for 3 h. By systematically comparing the crystalline phase, structure, morphological features, and photocatalytic properties of 3% Y-TiO-H with pure TiO, 3% Y-TiO, and TiO-H, the synergistic effect of Y doping and reduction of TiO was obtained. All samples show the single anatase phase, and no diffraction peak shift is observed. Compared with single-doped TiO and single-reduced TiO, 3% Y-TiO-H exhibits the best photocatalytic performance for the degradation of RhB, which can be totally degraded in 20 min. The improvement of photocatalytic performance was attributed to the synergistic effect of Y doping and reduction treatment. Y doping broadened the range of light absorption and reduced the charge recombination rates, and the reduction treatment caused TiO to be enveloped by disordered shells. The remarkable feature of reduced TiO by H is its disordered shell filled with a limited amount of oxygen vacancies (Os) or Ti, which significantly reduces the E of TiO and remarkably increases the absorption of visible light. The synergistic effect of Y doping, Ti species, and Os play an important role in the improvement of photocatalytic performances. The discovery of this work provides a new perspective for the improvement of other photocatalysts by combining doping and reduction to modify traditional photocatalytic materials and further improve their performance.