Electronic Structure of Si-Doped BN Nanotubes Using X-ray Photoelectron Spectroscopy and First-Principles Calculation
2008; American Chemical Society; Volume: 21; Issue: 1 Linguagem: Inglês
10.1021/cm802559m
ISSN1520-5002
AutoresYong Jae Cho, Changhyun Kim, Han Sung Kim, Jeunghee Park, Hyun Chul Choi, Hyun‐Joon Shin, Guohua Gao, Hong Seok Kang,
Tópico(s)MXene and MAX Phase Materials
ResumoSilicon (Si)-doped multiwalled boron nitride nanotubes (BNNTs) were synthesized via thermal chemical vapor deposition. Electron energy-loss spectroscopy revealed that 5% of Si atoms were homogeneously doped into the BNNTs. X-ray absorption and photoelectron spectroscopy measurements demonstrated that the Si−B and Si−N bonding structures are produced, where both structures reduce the π bonding states of the BN sheets. The valence band analysis indicates that the Si doping decreases the band gap by about 1.7 eV. The first principles calculation of the Si-doped double-walled BNNTs suggests two distinctive doping structures; contiguous Si−Si bonding structures along the tube axis and a local hollow nitrogen-rich pyridine-like structure with a lone electron pair. It also predicts that the 4% Si-doped defective structures reduce the band gap of the BNNTs by 1.6 eV, which is in qualitative agreement with our experimental results.
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