Surface effect on the bandgap of BN one-dimensional nanostructures

We have presented a comprehensive first-principles investigation of the structural stability and electronic structure of one-dimensional boron nitride (BN) nanostructures including nanowires (NWs), facet-nanotubes (FNTs), and nanoholes inside bulk BN. It was found that the binding energy E-b of these BN one-dimensional nanostructures satisfies a linear dependence relationship with the surface atom ratio lambda, and the size-dependence of their bandgap E-g exhibits abnormal behavior compared with that of II-VI and III-V semiconductor NWs and FNTs (note that these nanostructures do not contain AlN and GaN): the E-g of BN one-dimensional nanostructures decreases with decreasing size. These unusual properties are attributed to the effects of lambda and the negative/positive curvature radius alpha of NB NWs and NTs. (C) 2011 American Institute of Physics. [doi:10.1063/1.3622561]