Enhancement of N2O decomposition performance by N2O pretreatment over Ce-Co-O catalyst

Abstract A series of Ce-Co-O binary oxides catalysts were synthesized by co-precipitation methods and tested for catalytic decomposition of N 2 O. The catalyst with 10 mol% of Ce showed superior activity. Significant enhancement of decomposition performance over N 2 O-pretreated Ce-Co-O catalysts was observed. The fresh, N 2 O-pretreated Co 3 O 4 and Ce-Co-O catalysts were characterized by XRD, Raman, XPS, H 2 -TPR, TPD studies. It was found the deposited oxygen species (O ∗ ), which generated from the dissociation of N 2 O, was responsible for the enhancement by N 2 O pretreatment. Due to the excellent oxygen storage capacity of CeO 2 , deposited O ∗ could transfer from Co 3 O 4 crystallites to CeO 2 crystallites during the regeneration process of active sites. Pretreatment of N 2 O at high temperature resulted in much abundant deposited O ∗ on the surface. After cooling temperature, the accumulation of massive O ∗ would arouse another surface-to-N 2 O electron transfer route (from O ∗ to N 2 O), leading to the cleavage of the N O bond. Meanwhile, the results revealed that the existence of electron transfer from catalysts to N 2 O was possible.