Transition metal atom adsorptions on a boron nitride nanocage

We have applied density functional theory within B3LYP and M05 functionals to investigate the chemical functionalization of B12N12 nanocage with 3d transition metal (TM) atoms. Main focuses have been placed on configurations corresponding to the located minima of the adsorbates, corresponding adsorption energies, and the modified electronic properties of the cage. It was shown that there is linear correlation between the adsorption energies of the B3LYP and M05 as the results of M05 are higher than those of B3LYP, about 0.52 eV. Based on calculations, the most stable adsorption site is over the bond shared by a four- and a six-membered ring in the outer surface of cluster, in most cases. Based on the M05 results, the adsorption energies of the Sc, Ti, V, Co, and Fe are relatively high (> 1.51 eV) and those of Mn, Ni, and Cu calculated to be in the range of 1.00-1.22 eV. The Cr atom forms a weak bond with a boron atom of the B12N12 cluster, while Zn atom cannot be chemically adsorbed. Charge transfer from metals to cluster ascertained that the B12N12 plays as an electron-trapping center. Inducing certain impurity states within the electron density of states, the TM adsorption significantly reduces the HOMO-LUMO gap of cluster, ranging from 32 to 79 %.