Ce Doping Boosts the Photocatalytic Activity of Ultrathin Bi2MoO6 Nanosheets for Toluene Selective Oxidation

The generation of reactive oxygen species (ROS) fromO(2) is a critical step to boost the performance of photocatalytictolueneoxidation. However, the production of ROS is greatly limited by theserious recombination of charge carriers and the lack of O-2 adsorption sites. In this work, Ce-doped Bi2MoO6 ultrathin nanosheets with rich oxygen defects are prepared by aone-step hydrothermal method. The ultrathin structure promotes thelongitudinal transport of carriers to the surface. The introductionof Ce ions generates both Ce3+/Ce4+ redox ionpairs and oxygen defects in Bi2MoO6, where theformer promotes the transfer of photogenerated electrons and the latterenhances the adsorption of O-2, thereby producing more superoxideradicals (& BULL;O-2 (-)). Attributed tothese advantages, Ce-doped Bi2MoO6 ultrathinnanosheets exhibit excellent photocatalytic activity for toluene selectiveoxidation. The toluene conversion rate is 4422 & mu;mol & BULL;g(-1)& BULL;h(-1). The selectivity valuesof benzaldehyde and benzyl alcohol are 84.7 and 15.3%, respectively.In addition, the mechanism of photocatalytic selective oxidation oftoluene is further explored through a series of experiments.