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Volumn 131, Issue 13, 2009, Pages 4839-4845

The nature of radiative transitions in O-doped boron nitride nanotubes

Author keywords

[No Author keywords available]

Indexed keywords

BORON NITRIDE NANOTUBES; BORON OXIDES; FIRST PRINCIPLE CALCULATIONS; GAP STATE; RADIATIVE TRANSITIONS; STRUCTURAL PATTERN; STRUCTURAL UNIT; SUBSTITUTIONAL IMPURITIES; VIBRATIONAL PROPERTIES;

EID: 67949092683     PISSN: 00027863     EISSN: None     Source Type: Journal    
DOI: 10.1021/ja809550u     Document Type: Article
Times cited : (45)

References (48)
  • 19
    • 4243943295 scopus 로고    scopus 로고
    • Perdew, J. P.; Burke, K.; Ernzerhof, M. Phys. Rev. Lett. 1996, 77, 3865. ibid. 1997, 78, 1396.
    • Perdew, J. P.; Burke, K.; Ernzerhof, M. Phys. Rev. Lett. 1996, 77, 3865. ibid. 1997, 78, 1396.
  • 30
    • 67949123622 scopus 로고    scopus 로고
    • According the definition of Formula (1), the formation energy of a given defect system will vary for different reference with different binding energy. Formation energies of a3 a4 are calculated using (5, 5) BNNT as the reference system. But the calculated binding energy difference (per B-N pair) between (5, 5) and (10, 0) BNNT is as small as 68 meV, which will not change the absolute formation energy of the corresponding system. Therefore, the formation energies for a3 a4 O-adsorbed (5, 5) BNNT and h-BO O-doped (10, 0) BNNT configurations are comparable.
    • According the definition of Formula (1), the formation energy of a given defect system will vary for different reference with different binding energy. Formation energies of a3 a4 are calculated using (5, 5) BNNT as the reference system. But the calculated binding energy difference (per B-N pair) between (5, 5) and (10, 0) BNNT is as small as 68 meV, which will not change the absolute formation energy of the corresponding system. Therefore, the formation energies for a3 a4 O-adsorbed (5, 5) BNNT and h-BO O-doped (10, 0) BNNT configurations are comparable.
  • 38
    • 0003406744 scopus 로고
    • edited by Cardona, M, Fulde, P, Queisser, H. J, Springer-Verlag, New York
    • Madelung, O.; Introduction to solid state theory, edited by Cardona, M.; Fulde, P.; Queisser, H. J. (Springer-Verlag, New York, 1978).
    • (1978) Introduction to solid state theory
    • Madelung, O.1
  • 39
    • 67949122296 scopus 로고    scopus 로고
    • There are still posibilties that the low-energy peaks may arise from the excitons bound to impurity centers or dark excitons. We notice that the CL spectra of BNNTs were measured at room temperature. Under such a condition, excitons bound to impurities could be thermally dissociated and dark exciton related luminescence peaks would be very weak in intensity,11 which are against the experimental findings
    • There are still posibilties that the low-energy peaks may arise from the excitons bound to impurity centers or dark excitons. We notice that the CL spectra of BNNTs were measured at room temperature. Under such a condition, excitons bound to impurities could be thermally dissociated and dark exciton related luminescence peaks would be very weak in intensity,11 which are against the experimental findings.
  • 40
    • 67949125048 scopus 로고    scopus 로고
    • Simulation of photon emission spectra, such as CL spectra using first principle calculation is challenging. Based on experimental spectroscopic results, it is infered that radiative transitions in h-BO configuration should originate from the relaxation of the excited electrons from the conduction bands to the gap states. Therefore, the optical signals in the CL spectra will be close to the corresponding adsorption peaks in energy. Very recently, Lee et al.41 successfully synthesized the multiwalled BNNTs samples using boric oxide CVD method similar to synthetic techniques Han et al. used, A small adsorption peak at 3.7 eV was observed in their measured UV-visible absorption spectra. Under the similar growth condition, it is expected that h-BO O-doped impurity may also exist in BNNT samples of Lee et al, which can give arise low-energy adsorption peak. Such an adsorption peak is very close to the luminescence peak of the CL spectra in energy, therefore further v
    • Simulation of photon emission spectra, such as CL spectra using first principle calculation is challenging. Based on experimental spectroscopic results, it is infered that radiative transitions in h-BO configuration should originate from the relaxation of the excited electrons from the conduction bands to the gap states. Therefore, the optical signals in the CL spectra will be close to the corresponding adsorption peaks in energy. Very recently, Lee et al.41 successfully synthesized the multiwalled BNNTs samples using boric oxide CVD method (similar to synthetic techniques Han et al. used). A small adsorption peak at 3.7 eV was observed in their measured UV-visible absorption spectra. Under the similar growth condition, it is expected that h-BO O-doped impurity may also exist in BNNT samples of Lee et al. , which can give arise low-energy adsorption peak. Such an adsorption peak is very close to the luminescence peak of the CL spectra in energy, therefore further verifying our assumption.
  • 45
    • 84869564008 scopus 로고    scopus 로고
    • For a boroxol-hydride molecule with C3h symmetry, The A′and E″ phonon modes are not IR active in principle. However, bulk boron oxide characterizes the lower symmetry (C3 point group or P31 space group for h- B2O3), where both A and E modes are IR active. Considering the following transformation: A′ A″ ⇀ A; E′ E″⇀ E, all vibrational modes obtained in boroxol- hydride molecule should be IR active.
    • For a "boroxol-hydride" molecule with C3h symmetry, The A′and E″ phonon modes are not IR active in principle. However, bulk boron oxide characterizes the lower symmetry (C3 point group or P31 space group for h- B2O3), where both A and E modes are IR active. Considering the following transformation: A′ A″ ⇀ A; E′ E″⇀ E, all vibrational modes obtained in "boroxol- hydride" molecule should be IR active.


* 이 정보는 Elsevier사의 SCOPUS DB에서 KISTI가 분석하여 추출한 것입니다.