Effect of γ-Al2O3 substrate on NO2 interaction with supported BaO clusters

BaO oxide is the main storage component of the NOx storage and reduction catalysts. Herein, the interactions between the NO2 molecule and the unsupported as well as γ-Al2O3 supported BaO clusters have been studied using the first principle density functional theory calculation. Our results indicated that there is a strong synergetic effect involving both the BaO clusters and the surface of the γ-Al2O3 substrate toward NO2 adsorption. The interfacial region between the monodispersed BaO cluster and the substrate surface that allows NO2 to bond with the cluster and the surface simultaneously was shown to be optimal for NO2 adsorption.