Molecular Charge Transfer: A Simple and Effective Route To Engineer the Band Structures of BN Nanosheets and Nanoribbons

The electronic properties of BN nanosheets and nanoribbons doped with organic molecules with strong electron-donating or accepting abilities were investigated by means of density functional theory computations. The interfacial charge transfer between BN nanosheets and the acceptor (tetracyanoquinodimethane, TCNQ) or donor (tetrathiafulvalene, TTF) molecule significantly reduces the intrinsic wide band gap of pristine BN nanosheets and consequently results in a p - or n -type semiconductor, respectively. Similar behavior is observed for both zigzag and armchair-edged BN nanoribbons. These findings suggest a simple and effective route to tune the electronic properties of BN materials in a wide range and also facilitate the design of BN-based molecular electronics.