Metal–organic framework-derived CeO(2)–ZnO catalysts for C(3)H(6)-SCR of NO: an in situ DRIFTS study

Metal–organic framework (MOF)-based derivatives have attracted an increasing interest in various research fields. Here, we synthesized CeO(2)–ZnO catalysts through the complete thermal decomposition of the Ce/MOF-5 precursor. The catalysts were characterized using XRD, FTIR, TG-DSC, SEM and H(2)-TPR. It is found that the as-prepared CeO(2)–ZnO is favorable for strengthening the interaction between Ce(4+) and Zn(2+). A significant improvement in the catalytic performance for C(3)H(6)-SCR of NO was found over the Ce-doped catalysts with the highest N(2) yield of 69.1% achieved over 5% CeO(2)–ZnO. In situ DRIFTS and NO-TPD experiments demonstrated the formation of monodentate nitrates, bidentate nitrates, chelating nitrite, nitro compounds, nitrosyl and C(x)H(y)O(z) species (enolic species and acetate) on the surface, followed by the formation of hydrocarbonate or carbonate as intermediates to directly generate N(2), CO(2) and H(2)O.