First-principles study of substitutional carbon pair and Stone-Wales defect complexes in boron nitride nanotubes

TL;DR

This study uses density functional theory to analyze how substitutional carbon pairs and Stone-Wales defects affect the properties of boron nitride nanotubes, revealing insights into defect formation energies and electronic states.

Contribution

It provides the first detailed computational analysis of substitutional carbon pairs and their Stone-Wales transformations in BNNTs, highlighting their energetic and electronic characteristics.

Findings

SW defect formation energy is 3.1 eV lower in C-doped BNNTs.

SW defect in C-doped BNNTs has higher experimental observability.

Localized electronic states are induced by carbon pair impurities.

Abstract

Using density functional theory, we study physical properties of boron nitride nanotubes (BNNTs) with the substitutional carbon pair defect. We also consider the Stone-Wales (SW) rearrangement of the C-C pair defect in the BNNT. The formation energy of an SW defect of the carbon dimer is approximately 3.1 eV lower than that of the SW-transformed B-N pair in the undoped BNNT. The activation energies show that the SW defect in the C-doped BNNT may be experimentally observed with a higher probability than in the undoped BNNT. Finally, we discuss the localized states originating from the carbon pair impurities.