Effect of adsorption sensitivity of armchair single-walled BN nanotube toward thiocyanate anion: A systematic evaluation of length and diameter effects

The first-principles calculations to investigate the adsorption behavior of thiocyanate anion (SCN−) on the external surface of H-capped (6, 0), (3, 3), and Al and Ga doped (3, 3) single-walled boron nitride nanotubes (SWBNNTs) has been performed. Binding energy and the equilibrium distance corresponding to the most stable state of SCN−/(3, 3) BNNT is found to be −1.747 eV and 1.546 A, respectively, which can represent mainly a polar covalent bond. The calculation results have shown that both doped aluminum and gallium can enhance the adsorption energy of SCN− into the (3, 3) BNNTs. For the SCN− /BNNT complexes, the energy gaps, NBO, dipole moments, natural atomic orbital occupancies and global indices have been computed using DFT theoretical method at B3LYP level and 6–31G** basis set. Finally, a novel type of the adsorbent that can be used to remove of SCN− anion has been reported.