Monometallic and bimetallic MOF-74-M (M = Mn, Co, Ni, Zn, MnCo, MnNi, and MnZn) catalysts were prepared by the solvothermal method for NH 3 -SCR. XRD, BET, SEM, and EDS-mapping tests indicate the successful synthesis of the MOF-74-M catalyst with uniform distribution of metal elements and large specific surface area, and the morphology is almost hexagonal. Adding Mn element to a single-metal catalyst can enhance activity, which is mainly because of the existence of various valence states of Mn so that it has excellent redox properties; the catalytic activity of water and sulfur resistance tests showed that the catalytic activity of MOF-74-M increases after adding a proper amount of SO 2 , mainly because of the increase in acidic sites. In situ DRIFTS results indicate that the low-temperature range of MOF-74-MnCo and MOF-74-Mn is dominated by the E−R mechanism and the high-temperature range is dominated by the L−H mechanism. The entire temperature range of MOF-74-Zn is dominated by the L−H mechanism. KEYWORDS: MOF-74, in situ DRIFTS, NH 3 -SCR, resistance of H 2 O and SO 2 , mechanism

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A series of doped rather than supported 3DOM Ce0.7Fe0.2M0.1O2 and bulk Ce0.7Fe0.2Cu0.1O2 catalysts are prepared for CO-SCR reaction. The formation of 3DOM structure not only improves the reduction performance and...

A series of MOFs with a 6-connected spn topology were synthesized Hf), Hf), Hf)). Through the in situ DRIFTS of NH 3 adsorptiondesorption, we found that the activated catalyst mainly contains Lewis acid sites. The effects of different organic ligands on the Lewis acid of the Zr 6 cluster were analyzed by XPS and NH 3 -TPD, and the relative Lewis acidity of the same metal was obtained: PCN-777 > MOF-808 > MOF-818. In the Py-FTIR results, we confirmed that MOF-818 has a higher acid site density. In the activity test, MOFs with mesoporous structure showed better catalytic activity under normal temperature and pressure. Among them, MOF-818 can still maintain a high degree of crystallinity after catalysis. Finally, we use density functional theory to propose the mechanism of the cycloaddition reaction of carbon dioxide and styrene oxide. The results show that the metal is coordinated with styrene oxide and halogens attack the β carbon of the epoxide.