Cooperative Spin Transition of Monodispersed FeN3 Sites within Graphene Induced by CO Adsorption.

The significance of identifying the fundamental mechanism of interactions between adjacent catalytic active centers has long been underestimated. Utilizing density functional theory calculations, we demonstrate controllable cooperative interaction between two nearby Fe centers embedded on nitrogenated graphene aided by CO adsorption. The interconnected adjacent Fe atoms respond cooperatively to CO molecules with communicative structural self-adaption and electronic transformation. The adsorbed CO changes not only the spin of the active site it is attached to but also that of its adjacent site. Consequently, the two adjacent Fe atoms feature unique oscillatory long-range spin coupling. Our theoretical investigation suggests cooperative communication between adjacent active sites on a single-atom catalyst is nontrivial.