Design of a Novel CeW/Fe‐TiO 2 Catalyst With High Oxygen Vacancy for Enhancing the Reactivity and SO 2 Resistance in Low‐Temperature NH 3 ‐SCR Reaction

ABSTRACT At present, the low temperature reactivity and resistance to SO 2 poisoning performance of environmentally friendly Ce‐based catalysts in the NH 3 ‐SCR reaction are still the main factor for practical application. In this work, Fe 3+ was introduced into the TiO 2 lattice using the hydrothermal method and substituted for part of Ti 4+ to form oxygen‐deficient structure in the Fe‐TiO 2 carrier, and active species CeW were loaded onto this defective carrier to test its catalytic performance. It was demonstrated that CeW/Fe‐TiO 2 catalyst with higher oxygen vacancy content exhibited better low temperature catalytic activity and superior resistance to SO 2 poisoning in NH 3 ‐SCR reaction. On the one hand, O v was able to optimize the electronic structure of the catalyst with electron enrichment in the Fe‐O v ‐Ti structural unit and electron transfer to surface Ce atom through oxygen vacancies, thus improving the chemical environment around Ce species. On the other hand, O v effectively adsorbed and activated oxygen and reactant molecule, and the NH 3 ‐SCR reaction proceeded through L‐H pathway, thus improving the low temperature performance of the CeW/Fe‐TiO 2 catalyst. Eventually, DFT results confirmed at the molecular level that the construction of oxygen vacancy defective structures effectively activated the reactant molecules and thus improved the catalyst efficiency.