Photocatalytic Activity under Weak Visible Light of Fe³⁺ Doped Mesoporous CeO₂

Abstract

Mesoporous CeO 2 and Ce–Fe–O solid solutions with high content of hydroxyl groups were successfully synthesized using triblock copolymer P123 as the template and Ce(NO 3 ) 3 ·6H 2 O and Fe(NO 3 ) 3 ·9H 2 O as raw materials. The resultant samples were characterized by X-ray diffraction (XRD), N 2 adsorption–desorption, Raman, UV–vis, transmission electron microscopy, and Fourier transform infrared spectroscopy techniques. The X-ray diffraction results indicated that the synthesized samples exhibited cubic CeO 2 without impurities. The photocatalytic activities of the prepared samples were evaluated by the decomposition of Rhodamine B (RhB) dye under weak natural light irradiation. The results showed that the photocatalytic efficiency of mesoporous CeO 2 is higher than that of bulk CeO 2, but lower than that of mesoporous Ce–Fe–O solid solution. Moreover, removing the template by extraction in ethanol leads to a much better photocatalyst compared with a calcinated one, due to the preservation of the hydroxyl groups on the mesoporous surface.