Preparation, Characterization And Photocatalytic Performance Of Novel Photocatalyst

Silver phosphate has good photocatalysis in visible light and has been extensively studied. But there are some defects, such as instability caued by hydrolysis and photosensitizing, which has limited practical application. AgBr has a certain photocatalytic activity under the visible region, but the photocatalytic activity needs to be improved. CeO2 belong to common photocatalyst, it has widely used because of reasonable price and environmental friendly. But CeO2 does not respond in the visible region. Visible light occupies a large part in sun light, which has limited application of CeO2.In this paper, an ultrasound-assisted method was used for synthesizing visible-light-driven Ag3PO4CeO2 photocatalyst. And their structures were characterized respectively by X-ray diffraction (XRD), transmission electron microscope (TEM), ultraviolet-visible absorption spectroscopy (UV-vis), fluorescence spectroscopy (PL), and other means. Through the photocatalytic degradation of methyl blue solution, we tested their photocatalytic performances. Results show that, under the 300W Xe lamp, ultrasonic treatment 60min, the best composite ratio of Ag3PO4/CeO2 photocatalyst is 3:5. And compared to CeO2 and Ag3PO4, Ag3PO4CeO2 has greatly improvement on the photocatalytic oxidation activity performance. After 20 minutes’reaction, the MB degradation rate was above 95%. The substrate’initial concentration matters has been syudied, which means the higher the substrate’initial concentration was, the worse the catalyst degradation efficiency was. The degradation rate of catalysts showed good stability. Hydroxyl radical plays a major role in this reaction. The cause of the enhanced activity is effectively suppressing the recombination of photogenerated charges, improving the photocatalytic performance under visible light.In addition, another photocatalyst of AgBr/CeO2 has been studied, it was characterized by X-ray diffraction (XRD), transmission electron microscope (TEM), ultraviolet-visible absorption spectroscopy (UV-vis), fluorescence spectroscopy (PL). AgBr/CeO2 has responsed in the visible region. Through the photocatalytic degradation of rhodamine B under visible light, the best composite ratio of AgBr/CeO2 photocatalyst is 3:5, and AgBr/CeO2 also have good photocatalytic degradation efficiency on MB. The CeO2, AgBr and AgBr/CeO2 has characterized by PL, the result show AgBr/CeO2 has effectively suppressed the recombination of photogenerated electron and hole in the process of photocatalytic reaction. So the photocatalytic performance is improved under visible light.