CO 2 and H 2 Activation on Zinc-Doped Copper Clusters.

Here we systematically investigate the CO 2 and H 2 activation and dissociation on small Cu n Zn 0/+ (n=3-6) clusters using Density Functional Theory. We show that Cu 6 Zn is a superatom, displaying an increased HOMO-LUMO gap and is inert towards CO 2 or H 2 activation or dissociation. While other neutral clusters weakly activate CO 2 , the cationic clusters preferentially bind the CO 2 in monodentate nonactivated way. Notably, Cu 4 Zn allows for the dissociation of activated CO 2 , whereas larger clusters destabilize all activated CO 2 binding modes. Conversely, H 2 dissociation is favored on all clusters examined, except for Cu 6 Zn. Cu 3 Zn + and Cu 4 Zn, favor the formation of formate through the H 2 dissociation pathway rather than CO 2 dissociation. These findings suggest the potential of these clusters as synthetic targets and underscore their significance in the realm of CO 2 hydrogenation.