Tuning SnO2Surface Area for Catalytic Toluene Deep Oxidation: On the Inherent Factors Determining the Reactivity

To understand the fundamental aspects of SnO2catalytic materials and develop applicable catalysts for VOCs combustion, SnO2samples possessing stable and varied surface areas are controllably constructed and applied to toluene deep oxidation. By improving SnO2surface area, the Sn4+cation exposure is improved, thus increasing its surface acidity, which benefits toluene molecule adsorption and activation. Furthermore, more surface defects can be generated, hence inducing the generation of more abundant surface active oxygen sites, which is favorable for further oxidizing the adsorbed and activated toluene intermediates. Therefore, the intrinsic activity of SnO2is eventually promoted. The coexistence of both kinds of active sites is crucial for the reaction, and the concerted interaction between them controls the reaction performance. Catalysts with good activity, superior stability, and potent water vapor tolerance can be achieved by controllably constructing SnO2possessing large and stable surface areas, and supporting less amount of Pd onto it.