Flower-like Pt/Fe2O3–CeO2 Catalysts for Highly Efficient Low-Temperature Catalytic Oxidation of Toluene

A series of porous Pt/FexCey microflowers have been synthesized through a solvothermal method. The well-defined mesoporous structure promotes gas distribution as well as even dispersion of active species, thus exposing more active sites and improving the catalytic efficiency for low-temperature toluene removal. The catalyst composition can be regulated by changing the Fe/Ce molar ratio and Pt loading content. Among the samples, 1 wt % Pt/Fe3Ce1 performed the best, with a reaction temperature for 90% toluene conversion of 192 °C at a WHSV of 36,000 mL/(h·g). The synergistic effect of Fe2O3 and CeO2 promotes electron transfer and migration of oxygen species. Addition of Pt enhances the mobility of lattice oxygen, generating a high concentration of active surface lattice oxygen, which facilitates toluene removal. The Mars–van Krevelen model could be applied to explain the mechanism of toluene oxidation over these Fe-based catalysts.