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

Abstract

An ab initio density functional study was performed investigating the adsorption of CO2 on neutral boron Bn (n = 10–13) clusters that are 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 B12, 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 B11 and B13 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.