Mechanism Research on Photocatalytic Degradation of Organic Waste-water by Ce-Ti- graphene Composite

摘要

Introducing a third kind of materials in the binary system of TiO2/ graphene to synthesize ternary system of dopant /TiO2/ graphene is another main measure to improve the photocatalytic properties of the composites, and we can use the properties of dopants to enhance the synergistic effect of these three components. In this paper, the influence of micro mechanism of a series of self-made ternary system of CeO2 /TiO2/ graphene photocatalysts on their activity was studied by the instruments such as SEM, FT-IR, Raman spectroscopy, XPS, UV-Vis DRS, and PL. The results show that the optical absorption properties of TiO2 are modified by loading CeO2 or graphene, and by loading the same mass, the effect of graphene on the increase of optical response range of the composites is better than that of CeO2. Furthermore, the optical response range of the ternary system of CeO2-TiO2-RGO composite photocatalysts was the maximum. And the addition of CeO2 or graphene affects the recombination of the photoelectron-hole to a certain extent, but it is weaker than the synergistic effect of graphene and CeO2 on preventing the recombination of photoelectron-hole pairs. And in the ternary system, with the content of CeO2 in the range from 0%-10%, the more the content of CeO2 is, the more obvious the synergistic effect is, and the lower the electron hole recombination probability is. The micromechanism detective results confirmed the photocatalysis experiments results that, the photocatalytic performance of the ternary system of CeO2-TiO2-RGO composite photocatalysts is better than that of the binary system of either CeO2-TiO2 or TiO2-RGO composite photocatalysts, and its photocatalytic performance is improved with the increase of the CeO2 content in the ternary system.