Influence of axial tensile strain on the electronic and structural properties as well as NO gas sensitivity and reactivity of C-doped SW-BNNTs

The insulating character of BNNTs strongly imposes a great restriction on their applicability in nano-electronic devices. Therefore, it is desirable to find the practical routes for reducing the H-L gap. In this work, we demonstrate that the structural and electronic properties of the C-doped SW-BNNT can be significantly engineered and tuned by applying the axial tensile strain. Defect formation energies, cohesive energies, dipole moments, NBO charges, and global reactivity descriptors for un-doped SW-BNNT and C-1.3-doped SW-BNNTs are calculated upon the axial strain. The B3LYP/6-31 +G(d) calculated H-L gap for five C-doped SW-BNNTs are expected to be smaller than that of un-doped SW-BNNT. At 10% axial tensile strain, C-B NT is a suitable conductance with a 1.947 eV H-L gap. The decrease in the H-L gap for 2C-doped C-N,C-B (-0.839 eV) NT within 15% strain is greater than 1C- and 3C-doped SW-BNNTs. In the second part,of this work, reactivity and the sensitivity of strained C1-2-doped SW-BNNTs toward NO gas were evaluated at M06-2X/6-31 ++G(d,p) level of theory. Optimized structures, molecular graphs, adsorption energies (AE), dispersion corrected AEs, H-L gap, NBO charges, charge transfer values, density of states and electrostatic potentials were calculated. The strained C1-3-doped SW-BNNTs showed an increased ability for the sensitivity and adsorption of NO molecule, as compared with unstrained doped SW-BNNT. In general, the C-N,C-B NTs have practically less potential for the adsorption of NO molecule than C-B and C-N ones. (C) 2017 Elsevier B.V. All rights reserved.