标题：Facile in situ synthesis of visible-light plasmonic photocatalysts M@TiO2 (M = Au, Pt, Ag) and evaluation of their photocatalytic oxidation of benzene to phenol
作者：Zhaoke Zheng;Baibiao Huang;Xiaoyan Qin
作者机构：[Zheng, Z] State Key Lab of Crystal Materials, Shandong University, Jinan 250100, China;[ Huang, B] State Key Lab of Crystal Materials, Shandong Unive 更多
通讯作者地址：[Huang, BB]Shandong Univ, State Key Lab Crystal Mat, Jinan 250100, Peoples R China.
来源：Journal of Materials Chemistry: An Interdisciplinary Journal dealing with Synthesis, Structures, Properties and Applications of Materials, Particulary Those Associated with Advanced Technology
摘要：We developed a facile in situ method of preparing noble-metal plasmonic photocatalysts M@TiO2 (M = Au, Pt, Ag). In this method, the UV irradiation of TiO2 powder dispersed in absolute ethanol generates some Ti~(3+) ions on the surface of TiO2 particles and these Ti~(3+) ions, upon addition of a noble-metal salt in the dark, reduce the metal cations to deposit metal nanoparticles on the TiO2 surface. This Ti~(3+)-ion-assisted synthesis leads to a homogeneous loading of noble-metal nanoparticles on the surface of TiO2 particles, which allows photocatalytic reactions to take place under visible-light on the whole TiO2 surface. Among the three photocatalysts M@TiO2 (M = Au, Pt, Ag), Au@TiO2 exhibits a high yield (63%) and selectivity (91%) for the oxidation of benzene to phenol in aqueous phenol. For this photocatalytic reaction, our study suggests a mechanism in which the visible-light absorption by the Au nanoparticles causes electron transfer from the Au nanoparticles to the TiO2 particle, and the electron-depleted Au oxidizes phenoxy anions to form phenoxy radicals that oxidize benzene to phenol.