The tuned selective catalytic reduction behaviors of NO over the Pt/CeO2 catalysts by preferentially exposing different facets of CeO2 supports

Abstract

For the Pt catalysts supported on CeO2 nanosheet (NS), nanopolyhedron (NP) and nanorod (NR) with preferentially exposed {100}, {111} and {110} facets, respectively, the NO conversion and N2 selectivity for NO + CO reaction at 100–250 °C exhibit the order as Pt/CeO2-NS{100} > Pt/CeO2-NP{111} > Pt/CeO2-NR{110}. The higher surface concentration of oxygen vacancies on CeO2 (NS) can promote the dissociation of NO and result in the highest performance of Pt/CeO2-NS{100} catalyst. Moreover, CO intensively chemisorbs on the Pt2+ ions on CeO2 (NR) support, suppressing the dissociative chemisorption of NO and leading to lower reaction performance of Pt/CeO2-NR{110} catalyst.

Keywords

• NO + CO reaction
• Pt catalyst
• CeO2 support
• Different exposed facet
• Oxygen vacancy