DRIFTS study of the role of alkaline earths in promoting the catalytic activity of HC and NOx conversion over Pd-only three-way catalysts

作者：Yang, Linyan^*; Yang, Xue; Lin, Siyu; Zhou, Renxian

来源：Catalysis Science & Technology, 2015, 5(3): 1495-1503.

DOI：10.1039/c4cy01385a

• IN-SITU DRIFTS
• SIMULATED EXHAUST CONDITIONS
• STORAGE CAPACITY
• NSR-CATALYSTS
• NA MODIFIERS
• NITRIC-OXIDE
• CO REACTION
• FT-IR
• REDUCTION
• ADSORPTION

To reveal the role of alkaline earths modification in promoting the catalytic activity of HC and NOx conversion, catalytic activity tests and DRIFT experiments under different reaction conditions were performed. The introduction of alkaline earths promotes the catalytic activities of both HC and NOx elimination under stoichiometric NOx-CO-HC-O-2 conditions, especially for Pd/CZBa, whereas it inhibits CO oxidation. In addition, the operation window of NOx conversion is also obviously widened as a result of enhanced NOx storage ability. DRIFTS results demonstrate that modification with alkaline earths improves the formation rate of nitrites and nitrates due to enhanced electron transfer and oxygen mobility, as well as the dissociation of NO species on the active metal, which increases the storage ability and reduction performance of NOx. On the other hand, the doping of alkaline earths could weaken the inhibiting effect arising from strongly bonded HC species on NO adsorption and dissociation due to the promoted catalytic activity of HC deep oxidation, which promotes the reaction of CO and NOx at low temperature.

• 出版日期2015-3-1
• 单位浙江大学