Sub-stoichiometry on the A-site in a lanthanum-iron-manganese perovskite enhances the reactivity and nitrogen selectivity in the selective catalytic reduction of NO by CO.
The project focuses on mixed ionic-electronic conductors in a novel class of highly ordered, chemically and structurally highly complex oxide materials, e.g., on lanthanum-copper-manganese or lanthanum-iron-manganese basis for in situ activation through exsolution of small metal particles and the associated formation of metal-perovskite interfaces. The physico-chemical properties of the latter can be directly steered through synthesis and activation and therefore these interfaces exhibit the potential to replace existing noble metal-based materials in energy- and environmentally relevant reactions, such as the selective catalytic reduction of NO by CO. The key topic is retaining the structural stability and/or steering of the stability of the interface by simultaneously keeping beneficial catalytic properties (number and distribution of oxygen vacancies, surface and redox chemistry) under operational conditions. Through monitoring the structural or spectroscopic changes live under typical reaction conditions by in situ methods, we are able to gain fundamental insight into the structural and chemical dynamics of those materials and to establish unambiguous structure-activity relationships.