Single-Cation Catalyst: Ni Cation in Monolayered CuO for COOxidation

It is vital to differentiate catalytic properties between cationic and metallic single atoms at the atomic level. To achievethis, we fabricated well-defined cationic Ni atoms snugged in and metallic Ni atoms supported on monolayered CuO. The Ni cationsare chemically inert for CO adsorption even at 70 K but highly active toward O2dissociation at room temperature. The adsorbed Oatoms are active to oxidize incoming CO molecules from the gas phase into CO2, which follows the Eley-Rideal mechanism, incontrast to the Mars-van Krevelen mechanism on CuO-monolayer-supported metallic Ni atoms as well as our previously reportedAu and Pt model catalysts. This study helps understand the chemistry of a supported single-metal cation, which is of greatimportance in heterogeneous catalysis.

Automated summary

This study differentiates the catalytic properties between cationic and metallic single atoms. The results show that on monolayered CuO support, the reaction mechanism for CO conversion to CO2 is Eley-Rideal for cationic Ni atoms, while it is Mars-van Krevelen for metallic Ni atoms and previously reported Au and Pt model catalysts.