Computational Study of Hydrogen Molecules Adsorption on Boron Nitride with/without Adopted by One of Elements from Group IV

Abstract

In this study, we reported the adsorption of two hydrogen (H2) molecules on six boron nitride (BN) studied models with or without adopted by one of the elements from Group IV. By employing the computational method of density functional theory (DFT), the hydrogen binding energies and electronic structures were analyzed and discussed. The computed results presented that the most favorable adsorption sites were found for the two H2 molecules in all studied systems. The computed optimal binding energies of all BN studied systems were determined to be 0.01 eV – 0.05 eV per H2 molecule, which is smaller than that of the previous literature study. Moreover, the energies of HOMO–LUMOs were predicted in the range of 1.64 eV – 6.18 eV. For the surface plots of molecular electrostatic potentials (MEPs), the H atoms at the N–edges possess the most positive electrostatic potentials, while the negative electrostatic potentials fall in the atoms of H at the B–edges. A similar trend was presented on the distribution of atomic charge. Using the scheme of Mulliken population analysis (MPA), there are two different charge values on the atom of H in this study. The H atoms at the B–edges possess the negative charges, whereas the positive charge values were found on the atoms of H at the N–edges. In addition, the findings also noted that the positive charge values were presented for all B atoms in the study. While the negative charges fall in the atoms of N.