Understanding Practical Catalysts Using a Surface Science Approach:  The Importance of Strong Interaction between BaO and Al₂O₃ in NO<i>_x</i> Storage Materials

Abstract

High Resolution Image Download MS PowerPoint Slide The interaction of NO 2 with BaO/Al 2 O 3 /NiAl(110) model NO x storage materials was investigated at BaO coverages corresponding to practical systems. The results obtained from these model systems show excellent correlation with those of practical systems. We found a specific, strong interaction between BaO and Al 2 O 3, and this interaction profoundly influences the NO x chemistry. BaO readily forms a Ba−aluminate-like surface phase, and upon the interaction with NO 2, Ba ions are pulled out from this surface layer to form Ba(NO 3 ) 2 clusters.