A comparative study on the activity and adsorption of bimetallic MOF-derived Me-Cu/TiO2 (Me=Fe, Co, Ni) for low-temperature selective catalytic reduction of NO by CO

The catalytic activity, adsorption and synergistic effect over bimetallic MOF derivatives with different dopant metal were systemically compared. A series of Me-Cu/TiO 2 (Me=Fe, Co, Ni) derived from bimetallic Me/Cu-BTC MOFs were fabricated via a sacrificing template method and applied for CO-SCR. Among the bimetallic catalysts, Fe-Cu/TiO 2 presented the best low-temperature of nearly 100% NO conversion from 150 °C to 350 °C with good NO selectivity. For Me-Cu/TiO 2 (Me=Fe, Co, Ni), the productions of crucial Cu + intermediate were determined to be 51.17%, 50.45%,49.4% by XPS, which were consistent with their catalytic activity results. The superior redox behavior of Fe-Cu/TiO 2 can be attributed to its higher Oβ / (Oα +Oβ) ratio of 32.90% and the higher Me 2+ / Me 3+ ratio of 1.79. In situ infrared analysis revealed that the Fe doping not only improved the formation and stability of nitrate species, but also enhanced the quantity of Lewis acid sites by forming Cu + -CO. Furthermore, a possible low-temperature Langmuir-Hinshelwood (L-H) mechanism over Me-Cu /TiO 2 (Me=Fe, Co, Ni) was proposed.