Topology and Electronic Structure of Onion-Like Carbon and Graphite/Diamond Nanocomposites
Full article
| Общее |
Language:
Английский,
Genre:
Full article,
Status:
Published,
Source type:
Original
|
| Conference |
2001 MRS Fall Meeting & Exhibition, Symposia U/V – Nanophase and Nanocomposite Materials IV
25-30 Nov 2001
,
Boston, Massachusetts
|
| Journal |
Materials Research Society Symposium Proceedings
ISSN: 0272-9172
|
| Output data |
Year: 2002,
Volume: 703,
Pages: 381-386
Pages count
: 6
DOI:
10.1557/PROC-703-V9.22
|
| Authors |
Bulusheva L.G.
1
,
Okotrub A.V.
1
,
Kuznetsov V.L.
2
,
Chuvilin A.L.
2
,
Butenko Y.V.
2
,
Heggie M.I.
3
|
| Affiliations |
| 1 |
Institute of Inorganic Chemistry SB RAS, Novosibirsk, RUSSIA
|
| 2 |
Boreskov Institute of Catalysis SB RAS, Novosibirsk, RUSSIA
|
| 3 |
School of Chemistry, Physics and Environmental Science, University of Sussex at Brighton, UK
|
|
Funding (5)
|
1
|
Civilian Research and Development Foundation
|
REC-008
|
|
2
|
International Association for the Promotion of Co-operation with Scientists from the New Independent States of the Former Soviet Union
|
97-1700
|
|
3
|
Russian Foundation for Basic Research
|
00-03-32463
|
|
4
|
Russian Foundation for Basic Research
|
00-03-32510
|
|
5
|
International Association for the Promotion of Co-operation with Scientists from the New Independent States of the Former Soviet Union
|
01-237
|
Annealing of nanodiamond at moderate temperature makes it possible to produce structures being intermediate in the carbon transformation from sp3- to sp2-state (graphite/diamond nanocomposites) and onion-like carbon (OLC). Electron microscopy shows such structures involve cage shells with spacing close to graphite. X-ray emission spectroscopy has been applied to examine the electronic structure of OLC and graphite/diamond nanocomposites. The CKα-spectra of OLC produced in the temperature range of 1600-1900 K were found to be markedly different from the spectrum of particles formed at 2140 K and characterized by better ordering of graphitic shells. The latter spectrum was shown to be very similar to the CKα-spectrum of polycrystalline graphite, while the former ones exhibited a significant increase of high-energy maximum that might be caused by the holed defect structure of graphitic networks forming at the intermediate annealing temperatures. To interpret experimental spectra, the quantum-chemical semiempirical AM1 calculation of icosahedral C540 cage and that with holed defects was carried out. The lack of at least 22% atoms in an internal carbon cage was found to be essential to provide an increase of density of high-energy electronic states similar to that observed in the spectrum of OLC produced at 1900 K.