Mechanism for NO2 Storage in Ceria Studied By Combined in situ Raman/FT-IR Spectroscopy

In the context of NSR catalysts for lean-burn engines in situ Raman spectroscopy combined with FT-IR gas phase analysis was used to elucidate the NO₂ storage mechanism in ceria. NO₂ exposure induces an immediate increase in the ceria reduction degree accompanying nitrate formation. Two parallel nitrate formation pathways are identified.