First principles study of H2O and NH3 adsorption on the pristine and B-doped Al12N12 nanocluster

Adsorption of NH3 and H2O molecules on pristine and B–doped Al12N12 nano–cage was investigated using density functional theory, by means of B3LYP and X3LYP functionals. Both NH3 and H2O molecules were found to bind to an Al atom of Al12N12 via chemisorption, releasing energies ranging from –1.48 to –1.53 and –1.16 to –1.22 eV, respectively. The binding energies of X3LYP functional are somewhat larger than those of the B3LYP. The Morokuma–Kitaura energy decomposition approach reveals that the nature of these interactions is mainly electrostatic rather than covalent. The Al12N12 strongly adsorbs these molecules without any change in its electronic properties namely, these processes are electronically ineffectual. B–doping decreases the adsorption energies of the studied molecules whereas it cannot affect the sensitivity of the Al12N12 towards them.