Development of a thermally stable Pt catalyst by redispersion between CeO2and Al2O3

For catalytic systems consisting of Pt as the active component and CeO2-Al2O3as the support material, the metal-support interaction between the Pt and CeO2components is widely applied to inhibit aggregation of Pt species and thus enhance the thermal stability of the catalyst. In this work, a highly thermostable Pt catalyst was prepared by modifying the synthesis procedure for conventional Pt/CeO2/Al2O3(Pt/Ce/Al) catalyst, that is, the CeO2component was introduced after deposition of Pt on Al2O3. The obtained CeO2/Pt/Al2O3(Ce/Pt/Al) catalyst exhibits significantly different aging behavior. During the hydrothermal aging process, redispersion of Pt species from the surface of Al2O3to the surface of CeO2occurs, resulting in a stronger metal-support interaction between Pt and CeO2. Thus, the formed Pt-O-Ce bond could act as an anchor to retard aggregation of Pt species and help Pt species stay at a more oxidative state. Consequently, excellent reduction capability and superior three-way catalytic performance are acquired by Ce/Pt/Al-a after hydrothermal aging treatment.

Duke Scholars

Author Li Lan Molecular Genetics and Microbiology