Investigation on NH3‑SCR performance and low N2O formation mechanism over MIL‑100(FeMn) catalyst

Fe-based metal–organic frameworks (Fe-MOFs) have attracted extensive attention in the field of NH 3 -SCR denitrification due to their environmental friendliness and tunable redox properties. In this work, the catalytic performance of bimetallic MIL-100(FeMn) catalysts was systematically investigated, and a comparative study was further conducted with conventional FeMnO x catalysts synthesized via the co-precipitation method. The experimental results reveal that MIL-100(FeMn) catalyst achieves a NO x conversion of 91% at 275 ℃, and maintains a high N 2 selectivity of 94%–99% over the entire tested temperature range. Such excellent performance is attributed to the highly dispersed metal sites, moderate surface acidity and appropriate redox properties of the material. Moreover, the as-prepared catalyst can effectively restrain the side reactions of excessive NH 3 oxidation and deep NO oxidation. In-situ DRIFTS characterization confirms that the NH 3 -SCR reaction over MIL-100(FeMn) follows the Eley-Rideal mechanism, which inhibits the formation of inert nitrate species and thereby realizes the simultaneous improvement of catalytic activity and N 2 selectivity. This work provides a novel insight and experimental reference for the exploitation of high-performance low-temperature de-NO x catalysts with low N 2 O emission.