Synergistic Effect of Reactive Oxygen Species in Photothermocatalytic Removal of VOCs from Cooking Oil Fumes over Pt/CeO2/TiO2

The volatile organic compounds (VOCs) from cooking oil fumes are very complex and do harm to humans and the environment. Herein, we develop the high-efficiency and energy-saving synergistic photothermocatalytic oxidation approach to eliminate the mixture of heptane and hexanal, the representative VOCs with high concentrations in cooking oil fumes. The Pt/CeO2/TiO2 catalyst with nanosized Pt particles was prepared by the simple hydrothermal and impregnation methods, and the physicochemical properties of the catalyst were measured using numerous techniques. The Pt/CeO2/TiO2 catalyst eliminated the VOC mixture at low light intensity (100 mW cm(-2)) and low temperature (200 degrees C). In addition, it showed 25 h of catalytic stability and water resistance (water concentration up to 20 vol %) at 140 or 190 degrees C. It is concluded that O-2 picked up the electrons from Pt to generate the O-center dot(2)- species, which were transformed to the O-2(2-) and O- species after the rise in temperature. In the presence of water, the (OH)-O-center dot species induced by light irradiation on the catalyst surface and the (OOH)-O-center dot species formed via the thermal reaction were both supplementary oxygen species for VOC oxidation. The synergistic interaction of photo- and thermocatalysis was generated by the reactive oxygen species.