Active Site Identification and Modification of Electronic States by Atomic-Scale Doping To Enhance Oxide Catalyst Innovation

Identification of the catalytic active site is critical in the design and development of advanced heterogeneous catalysts. Many high-precision experimental techniques, as well as computational methods, have been developed to address this problem, but identifying the active site for composite oxide catalysts remains a challenging task because of their complexity and indiscernible microstructures. Herein, we provide a key new insight into the active site within a composite oxide catalyst by investigating an iron-based oxide catalyst with complex components. The dopant atoms with octahedral coordination located at substitution sites in the Fe2O3 lattice tune the electronic structure of the adjacent iron atoms, which act as the active sites that lead to enhanced catalytic activity. This atomic-scale doping is different from the emerging single-atom catalyst concept, in which the single atom on the support is the active site, and which provides an alternative methodology of improving the activity of heterogeneous catalysts with maximized heteroatom efficiency.