P改性Pt/CeO2单原子催化剂的CO低温氧化催化性能研究OA

CO is a widely distributed air pollutant that poses a significant threat to the environment and human health.At present,CO thermal catalytic oxidation is considered to be the most energy-efficient and efficient conversion method,but the Pt/CeO2 catalyst prepared by traditional impregnation method is close to the limit of its catalytic performance.For supported Pt/CeO2 single-atom catalyst,the surface properties of the support and the local coordination environments of the metal single-atom play an important role in its catalytic performance.The P-modified single-atom catalyst Pt/CeO2-y POx was prepared by the introduction of phosphoric acid by impregnation,and the structure of the Pt/CeO2-y POx was characterized by XRD,CO-DRIFTS,FT-IR and so on,and the catalytic performance was studied.The results show that when m(phosphoric acid)/m(CeO2)≤0.0850,Pt exists in the catalyst as a single atom.For Pt/CeO2-y POx,P—O—Pt coordination is formed,and its total amount of Lewis acid sites increases,and a trace amount of Brønsted acid is also generated,which is beneficial for the CO adsorption.At the same time,the reduction performance of the catalyst is improved,so the catalytic performance for low-temperature CO oxidation is significantly improved.Pt/CeO2-0.085POx shows the best catalytic performance,reducing the CO conversion temperature to 40℃and reducing the temperature at which the CO conversion rate reaches 100%to 110℃.