X-ray Photoelectron Spectroscopy and First Principles Calculation of BCN Nanotubes
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- 作者：Shin Young Kim ; Jeunghee Park ; Hyun Chul Choi ; Jae Pyung Ahn ; Jin Qiang Hou ; Hong Seok Kang
- 刊名：Journal of the American Chemical Society
- 出版年：2007
- 出版时间：February 14, 2007
- 年：2007
- 卷：129
- 期：6
- 页码：1705 - 1716
- 全文大小：939K
- 年卷期：v.129,no.6(February 14, 2007)
- ISSN：1520-5126
文摘
Multiwalled boron carbonitride (BCN) nanotubes with two different structures were synthesizedvia thermal chemical vapor deposition; one has 10% C atoms homogeneously doped into BN nanotubes(B0.45C0.1N0.45 NTs), and the other has BN layers sheathed with 5-nm-thick C outerlayers (BN-C NTs).The electronic structures of the B, C, and N atoms were thoroughly probed by synchrotron X-rayphotoelectron spectroscopy and the X-ray absorption near-edge structure method. The B0.45C0.1N0.45 NTscontain a significant amount of B-C and C-N bonding with a pyridine-like structure (hole structure), whichreduces the 
bonding states of the B and N atoms. From the XPS valence band spectrum, the band gapwas estimated to be about 2.8 eV. In the BN-C NTs, the C and BN domains are separated without formingthe pyridine-like structure. Using the first principles method, we investigated the relative stabilities andelectronic structures of the various isomers of the double-walled (12,0)@(20,0) BCN NTs. The C-outerlayerBN nanotube structure is the most stable isomer, when there exist no defects in the tubes with B/N = 1.0(i.e., graphite-like structure). In addition, a reasonable model, which is characterized by the motives consistedof three pyridine-like rings around a hollow site, is presented for the local structure of C atoms in theB0.45N0.45C0.1 NTs. A considerable decrease of the band gap due to the 10% C doping was predicted,which was consistent with the experimental results.
bonding states of the B and N atoms. From the XPS valence band spectrum, the band gapwas estimated to be about 2.8 eV. In the BN-C NTs, the C and BN domains are separated without formingthe pyridine-like structure. Using the first principles method, we investigated the relative stabilities andelectronic structures of the various isomers of the double-walled (12,0)@(20,0) BCN NTs. The C-outerlayerBN nanotube structure is the most stable isomer, when there exist no defects in the tubes with B/N = 1.0(i.e., graphite-like structure). In addition, a reasonable model, which is characterized by the motives consistedof three pyridine-like rings around a hollow site, is presented for the local structure of C atoms in theB0.45N0.45C0.1 NTs. A considerable decrease of the band gap due to the 10% C doping was predicted,which was consistent with the experimental results.