The structural and electronic properties of amine-functionalized boron nitride nanotubes via ammonia plasmas: a density functional theory study

The reaction behavior of the chemical modification of boron nitride nanotubes (BNNTs) with ammonia plasmas has been investigated by density functional theory (DFT) calculations. Unlike previously studied functionalization with NH3 and amino functional groups, we found that NH2* radicals involved in the ammonia plasmas can be covalently incorporated to BNNTs through a strong single B-N bond. Subsequently, the H* radicals also involved in the ammonia plasmas would prefer to combine with the N atoms neighboring the NH2-functionalized B atoms. Our study revealed that this reaction behavior can be elucidated using the frontier orbital theory. The calculated band structures and density of states (DOS) indicate that this modification is an effective method to modulate the electronic properties of BNNTs. We have discussed various defects on the surface of BNNTs generated by collisions of N-2(+) ions. For most defects considered, the reactivity of the functionalization of BNNTs with NH2* are enhanced. Our conclusions are independent of the chirality, and the diameter dependence of the reaction energies is presented.