Nano-Carbon Materials: Fundamental Aspects and Applications

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Nano-Carbon Materials Fundamental Aspects and
Applications
Alexander N. Obraztsov Faculty of Physics, Moscow
State University E-mail obraz_at_polly.phys.msu.ru
Russian-French Workshop on Nanoscience and
Nanotechnologies , Lile, France, August 29-31,
2005
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Moscow State University
Department of Physics
Russian-French Workshop on Nanoscience and
Nanotechnologies , Lile, France, August 29-31,
2005
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Laboratory of Carbon Materials
Nano-Carbon
Russian-French Workshop on Nanoscience and
Nanotechnologies , Lile, France, August 29-31,
2005
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Chemical Vapor Deposition of Carbon Films
Gas mixture H2CH4101 Gas Pressure P10 kPa
Voltage V700V Current I4 A Substrate
Size 25x25 mm Material Si Temperature
T1000ºC
Russian-French Workshop on Nanoscience and
Nanotechnologies , Lile, France, August 29-31,
2005
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Chemical Vapor Deposition of Carbon Films
H2
CH4
CH C2
Gas mixture H2CH4101 Gas Pressure P10 kPa
Voltage V700V Current I4 A Substrate Size
25x25 mm Material Si Temperature
T1000ºC Carbon 41 (2004) 836
Russian-French Workshop on Nanoscience and
Nanotechnologies , Lile, France, August 29-31,
2005
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Chemical Vapor Deposition of Carbon Films
Raman spectrometer Jobin Yvon U1000
Cu-vapor laser
Spectrometer OceanOptics HR4000
Current source
CH4
H2
Rotary pump
Russian-French Workshop on Nanoscience and
Nanotechnologies , Lile, France, August 29-31,
2005
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Chemical Vapor Deposition of Carbon Films
Russian-French Workshop on Nanoscience and
Nanotechnologies , Lile, France, August 29-31,
2005
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In-situ optical characterisation of DC discharge
plasma
Typical images of dc discharges taken for pure
hydrogen (a) and hydrogen-methane gas mixtures
with 8 (b) and 25 (c) of CH4. The total gas
pressure is 80 Torr. Si wafer of 50 mm in
diameter is used as a substrate, which is located
on the anode in CVD reactor chamber. The images
are obtained at voltages 650 V (a), 750 V (b),
850 V (c). The discharge current is 7 A (a), 6 A
(b), and 5 A(c).
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In-situ OES of DC discharge in H2CH4
Typical OES for pure hydrogen (a) and for
hydrogen-methane gas mixture with 10 (b) and 25
(c) of methane. Total gas pressure is 80 Torr,
applied voltage is 650 V (a), 750 V (b), 850 V
(c). The discharge current is 7 A (a), 6 A (b),
and 5 A(c).
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Model of nano-graphitic carbon deposition
C2
C2
C2
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Initial C2 nuclei on the subtstrate surface may
form atomic chains rather than plates
due to orientation of unsaturated carbon
bonds. Than formation of tiny graphite
crystallites and is possible.
CNT formation may be initiated by the
nano-crystallite curvature at initial stage
or after reaching of some critical height.
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Nano-graphitic carbon structure peculiarities
SEM image of a conical scroll on surface of
nanostructured graphite-like CVD film. The inner
part of the scroll is seen trough the outer layer
indicating on its very small thickness.