Strong chemisorption of CO2 on B10-B13 planar-type clusters

An ab initio density functional study was performed investigating the adsorption of CO2 on neutral boron B-n (n = 10-13) clusters that arc characterized by planar and quasiplanar ground-state atomic structures. For all four clusters, we found large chemisorption binding energies, reaching 1.6 eV between CO2 and B-12 , with the adsorbed molecule oriented in the plane of the cluster and adsorbed along the cluster edge. A configuration with chemisorbed dissociated CO2 molecule also exists for B-11 and B-13 clusters. The strong adsorption is due to the bending of the CO2 molecule, which provides energetically accessible fully in-plane frontier molecular orbitals matching the edge states of the clusters. At the same time, the intrinsic dipole moment of a bent CO2 molecule facilitates the transfer of excess electronic charge from the cluster edges to the molecule.