Ligand Stabilized Ni1 Catalyst for Efficient CO Oxidation.

Supported single transition metal (TM1 ) catalysts have attracted broad attention in academia recently. Still, their corresponding reactivity and stability under reaction conditions are critical but have not well explored at the fundamental level. Herein, we use density functional theory calculation and ab initio molecular dynamics simulation to investigate the role of reactants and ligands on the reactivity and stability of graphitic carbon nitride (g-C3 N4 ) supported Ni1 for CO oxidation. We find out that supported bare Ni1 atoms are only metastable on the surface and tend to diffuse into the interlayer of g-C3 N4 . Though Ni1 is catalytically active at moderate temperatures, CO adsorption induced dimerization deactivates the catalyst. Hydroxyl groups not only are able to stabilize the supported Ni1 atom, but also increase the reactivity by participating directly in the reaction. Our results provide valuable insights on improving the chemical stability of TM1 by ligands without sacrificing the reactivity, which are helpful for the rational design of highly loaded atomically dispersed supported metal catalysts.