Electronic Structure and Reactivity of Boron Nitride Nanoribbons with Stone-Wales Defects.

Gradient-corrected density functional theory (DFT) computations were performed to investigate the geometry, electronic property, formation energy, and reactivity of Stone-Wales (SW) defects in zigzag-edge and armchair-edge boron nitride nanoribbons (BNNRs). The formation energies of SW defects increase with an increase in the widths of BNNRs and are orientation-dependent. SW defects considerably reduce the band gaps of BNNRs independent of the defect orientations. In addition, the local chemical reactivity of SW defects and edge sites in zigzag-edge and armchair-edge BNNRs was probed with the CH2 cycloaddition reaction. Independent of the nanoribbon types and the SW defect orientations, the reactions at SW defect sites are more exothermic than those at the center of perfect BNNRs, and the newly formed B-B and N-N bonds are the most reactive sites, followed by the 5-7 ring fusions.