Clustering-Evolved Frontier Orbital for Low-Temperature CO 2 Dissociation.

In this study, single Ni ₂ clusters (two Ni atoms bridged by a lattice oxygen) are successfully synthesized on monolayered CuO. They exhibit a remarkable activity toward low-temperature CO ₂ thermal dissociation, in contrast to cationic Ni atoms that nondissociatively adsorb CO ₂ and metallic Ni ones that are chemically inert for CO ₂ adsorption. Density functional theory calculations reveal that the Ni ₂ clusters can significantly alter the spatial symmetry of their unoccupied frontier orbitals to match the occupied counterpart of the CO ₂ molecule and enable its low-temperature dissociation. This study may help advance single-cluster catalysis and exploit the unexcavated mechanism for low-temperature CO ₂ activation.