Silica-assisted Pt1/CeO2 single-atom catalyst for enhancing the catalytic combustion performance of VOCs by inducing H2O activation

Abstract

Due to the competitive adsorption of water and reactants at the active sites, especially the water toxicity of platinum-based single-atom catalysts, it is of great importance to improve the low-temperature activity and the water resistance of catalysts for the catalytic combustion of benzene. In this work, it was found that constructing a SiO2 shell layer on the catalyst not only "immobilized" the Pt single atoms, but also effectively weakened the adsorption of H2O on the Pt active sites, which resulted in excellent water resistance of the Pt single-atom catalysts. The comprehensive characterization results demonstrated that the participation of water molecules in the catalytic oxidation reaction of benzene could be effectively promoted by enhancing the strong metal-support interactions (SMSI) at the core-shell interface, which would change the electronic structure of the catalyst surface. As a result, the Pt1/CeO2@SiO2-4 catalyst with a Pt-O-Si active interface exhibits good activity (T = 190 °C) as well as excellent water resistance under the wet condition (10 vol%). This project provides a promising strategy for the design of Pt-based core-shell catalysts with excellent water resistance.