Promoting Plasma Photocatalytic Oxidation of Toluene Via the Construction of Porous Ag–CeO2/TiO2 Photocatalyst with Highly Active Ag/oxide Interface

Abstract

Plasma-photocatalysis system (PPS) constructed by dielectric barrier discharge and TiO2 photocatalysts could realize toluene oxidation removal at low temperatures, but requires further enhancement in the performance due to the relatively poor activity of TiO2. We herein report that co-loading Ag and CeO2 on porous TiO2 can construct a active Ag–CeO2/TiO2 photocatalyst for the PPS, enabling the PPS to achieve promoted toluene conversion, CO2 selectivity and stability in toluene oxidation removal. The Ag–CeO2/TiO2 photocatalyst with porous microstructure and dispersed surface Ag particles can change the discharge mode, facilitating the interaction of plasma and photocatalysts in the PPS. We further disclose that the Ag/oxide interface can create highly active sites for surface oxidation reactions and enhances the separation of photoinduced electron-holes under the action of plasma. The intimate interaction between plasma and Ag–CeO2/TiO2 photocatalyst and enhanced surface/photocatalytic oxidation reactions on Ag/oxide interface result in the promoted performance of toluene oxidation. The creation of highly active metal/oxide interface on porous TiO2 photocatalyst may provide a strategy for the construction of high-efficiency PPS for VOCs removal.