LDH-derived preparation of CuMgFe layered double oxides for NH3-SCR and CO oxidation reactions: Performance study and synergistic mechanism

• Novel CuMgFeO catalyst derived from CuMgFe-LDH materials prepared by co-precipitation method. • The CuMgFeO catalyst exhibited excellent catalytic performance in both the NH 3 -SCR and CO oxidation. • The CuMgFeO catalyst possessed the redox ability and surface acidity concurrently. • The CO oxidation and NH 3 -SCR reaction mechanism was proposed based on in situ DRIFTS. • The mechanism related to the deactivation of CuMgFeO catalyst in the presence of SO 2 was revealed. The NH 3 -SCR and CO oxidation reactions provides a promising route for the synergistic removal of NO x and CO. Herein, a novel two-dimensional CuMgFeO layered double oxides by the co-precipitation method and employed it for the NH 3 -SCR and CO oxidation reactions. The catalytic activity results showed that the CuMgFeO sample reached 96.8 % NO conversion at 250 °C, and 100 % CO conversion in temperature of 200–300 °C. Impressively, the CuMgFeO catalyst showed outstanding N 2 selectivity, water resistance, and maintained splendid long-term catalytic stability. The superior NH 3 -SCR and CO oxidation activity of CuMgFeO catalyst can be related to the well dispersion of CuO species, higher reducibility, and abundance of acid sites. Meanwhile, XPS analysis indicated that the presence of electron transfer between the Cu 2+ and Fe 3+ redox cycles, as well as adsorbed oxygen on the sample surface were the main reactive oxygen species. The in situ DRIFT species indicate that the NH 3 -SCR reaction over CuMgFeO catalysts mainly complied with the E-R mechanism, while the CO oxidation followed the L-H mechanism. Finally, the deactivation mechanism of SO 2 was investigated by in situ DRIFT species, indicating that SO 2 hinders the NH 3 -SCR reaction through competition with NH 3 and NO x for adsorption sites and the formation of ammonium sulfate salts. This work provides insight into the simultaneous implementation of the NH 3 -SCR and CO oxidation reactions on a single catalyst, which is of great value for the future synergistic control of flue gas pollutants.