新型钙钛矿结构光催化剂的合成及性能研究-应用化学专业论文.docx

AbstractWith the development of society and the improvement of peoples living conditions, the environmental pollution and energy crisis have been become an important problem to threaten the lives of human. In recent years, photocatalytic water splitting to H2 and photodegradation of organic pollutants using solar energy has received a great deal of attention by semiconductors photocatalysts, it has been considered as one of the potential ways to alleviate the energy crisis and reduce environmental pollution. In this paper, we used sol-gel method and solvothermal method to synthesize the novel photocatalysts with perovskite structure, all of samples have been investigated the photocatalytic water splitting to H2 or photodegradation of organic pollutants.Sr2/3Zn1/3TiO3 (SZT) and Ba5/6Zn1/6TiO3 (BZT) with perovskite structure havebeen prepared by a facile sol-gel method, among which the A sites of ATiO3 (A=Sr and Ba) have partially replaced by zinc ions, respectively. The samples were characterized by powder X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscope (TEM), UV–vis diffuse reflectance spectroscopy (UV-Vis) and Roman spectroscopy. The results showed that the photocatalyst SZT and BZT loaded without cocatalysts have high activity for reduction of water to H2 with a small quantity of ethanol (~3 %) as a sacrificial electron reagent under ultraviolet light irradiation, the rates of H2 production were about 73.2 μmol·h-1·g-1 and 57.5 μmol·h-1·g-1 for SZT andBZT, respectively. Furthermore, the rates of H2 production were about 12.1 μmol·h-1·g-1and 2.9 μmol·h-1·g-1 for SZT and BZT in pure water. In addition, we firstly reported that BaTiO3 type (BZT) can split water to H2 in this paper. The preparation conditions, including gel temperature, drying time of gel, calcination temperature and increasing/cooling rate of temperature were optimized, the purpose of the optimization is to enhance the photocatalytic activity of catalys