Synergetic Charge Transfer and Spin Selection in CO Oxidation at Neighboring Magnetic Single-Atom Catalyst Sites

Deciphering the precise physical mechanism of interaction between an adsorbed species and a reactive site in heterogeneous catalysis is crucial for predictive design of highly efficient catalysts. Here, using first-principles calculations we identify that the two-dimensional ferromagnetic metal organic framework of Mn₂C₁₈H₁₂ can serve as a highly efficient single-atom catalyst for spin-triplet O₂ activation and CO oxidation. The underlying mechanism is via "concerted charge-spin catalysis", involving a delicate synergetic process of charge transfer, provided by the hosting Mn atom, and spin selection, preserved through active participation of its nearest neighboring Mn atoms for the crucial step of O₂ activation. The synergetic mechanism is further found to be broadly applicable in O₂ adsorption on magnetic X₂C₁₈H₁₂ (X = Mn, Fe, Co, and Ni) with a well-defined linear scaling dependence between the chemical activity and spin excitation energy. The present findings provide new insights into chemical reactions wherein spin selection plays a vital role.