Mesoporous Ce-Pr-O solid solution with efficient photocatalytic activity under weak daylight irradiation

In this study, the application of mesoporous CeO2 and Pr doped CeO2 (Cesingle bondPrsingle bondO) as photocatalysts for the degradation of Rhodamine B (RhB) from aqueous solution was investigated. Mesoporous CeO2 and Cesingle bondPrsingle bondO were prepared using SBA-15 as template. The resultant samples were characterized by XRD, N2 adsorption–desorption, Raman, UV–vis, TEM, FT-IR, and XPS techniques. The characterization results show that the synthesized Cesingle bondPrsingle bondO has a 2D hexagonal structure, similar to that of the template, and possesses numerous oxygen vacancies. It is worth mentioning that the visible light adsorption intensity of Cesingle bondPrsingle bondO is much higher than that of mesoporous ceria and bulk ceria, due to simultaneous formation of doping level and mesopores. The photodegradation of RhB illustrates that the synthesized mesoporous Cesingle bondPrsingle bondO, especially 45% Cesingle bondPrsingle bondO, performs excellent decolorization under weak daylight irradiation. Furthermore, a novel photodegradation mechanism was proposed based on the adsorption of H2O2 over the oxygen vacancy.