MHS 2012 in Nagoya: 5th November, 2012
Production of Carbon Nanotubes Yoshinori ANDO Dean of Faculty of Science and Technology Meijo University
名城大学 理工学部長 安藤義則 Department of Materials Science and Engineering, Meijo University Shiogamaguchi 1-501,Tempaku-ku, Nagoya 468-8502, Japan
[email protected]
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◎History of Carbon Nanotubes (CNTs) ◎ Production of Multi-walled Carbon Nanotubes (MWNTs) by Arc Discharge ◎ Production of Single Wall Carbon Nanotubes (SWNTs) by Arc Discharge ◎ CNT Growth from Camphor by CVD Method 2
History of Carbon Nanotubes (CNTs)
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What’s Carbon? Carbon： Element C
[Atomic number ６，mass number１２，１３]
One of high Clarke number elements Crystal made of Carbon Diamond 3D crystal
Amorphous Carbon
Graphite Carbon Nanotube Fullerene Charcoal 2D crystal
1D crystal
0D crystal
Amorphous
2 nm
Various Dimensions Carbon Isomers are listed.
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Carbon Nanotubes (CNTs) Carbon Nanotubes (CNTs)： Tubes made by Carbon Diameter is the order of nm
HR-TEM micrograph of CNTs S. Iijima: Nature, 354 (1991), 56.
Rolled co-axial graphene tubes : Side wall is projected as parallel lines symmetrical to tube axis
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The Original Paper of Carbon Nanotubes Sumio Iijima: “Helical microtubles of graphitic carbon”, Nature, 354 (1991), 56. ↑ Name of “carbon nanotubes” is not yet used here.
I am said to be the first farmer of carbon nanotubes, and Meijo Univ. is the birth place of carbon nanotubes！
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Tip of tube and bamboo basket model
Six pentagons close hemi-sphere Heptagon at corner B
S. Iijima, T. Ichihashi & Y.Ando: Nature, 356 (1992), 776.
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Fullerenes
Carbon Nanotubes
1970 First prediction of C60
1985 Discover of C60
Osawa
Kroto, Smalley
Green terms are related with Y. Ando
1990 Mass production of fullerenes Krätschmer et al.
1991 Discover of MWNTs 1993 Discover of SWNTs
Iijima Iijima & Ichihashi Bethune et al.
1996 Nobel Prize for Chemistry: Discover of Fullerene Kroto, Curl, Smalley
Graphene
1997 Mass producction of SWNTs by arc method Journet et al. 1999 Discover of carbon nanohorn
Iijima et al.
2000 Thinnnest 4Å MWNTs
Qin et al.
2003 Macroscopic net of SWNTs
Zhao et al.
2004 Super growth of SWNTs
Hata et al.
2004 Discover of Graphene
Geim, Novoselov
2005 DIPS growth of SWNTs
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2010 Nobel Prize for Physics: Discover of Graphene
Saito et al. Geim, Novoselov
Production of CNTs in Ando Lab Arc Discharge
1991～present (21st COE ’02 ～’07)
Thermal CVD
2000～present (21st COE ’02 ～’07)
MWNTs: First specimen of CNTs discovery 1991 Precursor: Camphor Yield of CNTs
CH4 >> He > Ar
1994
1. Catalyst: ferrocene (floating catalyst)
Predominance of H2 ambient gas 1997
Substrate: quartz plate
4Åinnermost tube in H2–arc MWNT 2000
High yield of vertically aligned MWNTs 40mg per run (20 min reaction) 2002
Characteristic Raman spectra 2002
2001
Carbon chain in H2–arc MWNT 2003
Patterned growth of aligned MWNTs on Co/Si & Ni/Si substrates 2003
3Åinnermost tube in H2–arc MWNT 2004
2. Catalyst: Fe-Co (supported catalyst)
SWNTs: AC arc to produce SWNTs Mass production of SWNTs, APJ
1999 2000
Macroscopic web (～30cm) of SWNTs 2003
Support: zeolite powder
2003
High yield of MWNTs with narrow diameter distribution at 650℃ 2004 SWNTs & DWNTs at 900 ℃
2004
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Production of Multi-walled Carbon Nanotubes (MWNTs) by Arc Discharge
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Production of CNTs by DC Arc Discharge
Apparatus for mass production of fullerenes AC resistive heating W. Krätschmer et al., Nature, 347 (1990), 354.
The original apparatus for producing CNTs DC arc discharge Y. Ando & S. Iijima: Jpn. J. Appl. Phys., 32(1993), L107.
Apparatus producing ultrafine particles of SiC DC arc discharge Y. Ando & M. Ohkohchi, J. Cryst. Growth, 60(1982), 147.
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Cathode deposit obtained by DC arc evaporation
Optical photo of a section of cathode deposit Y. Ando & S. Iijima: Jpn. J. Appl. Phys., 32(1993), L107.
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SEM micrograph of deposit: CNTs and nanoparticles
Model of Multiwalled Carbon Nanotubes (MWNTs)
Double wall carbon nanotube (DWNT)
by S. Iijima
Four walls carbon nanotube an example of MWNTs
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Production of MWNTs in various kinds of gases
He: 100Torr
Ar: 100Torr
CH4: 100Torr
Among these three gases, CH4 gas (including H-atom) is the best. This is the essential difference between CNT and fullerene synthesis. Fullerene can’t be formed in gas including H-atom. Y. Ando: Fuller. Sci. & Tech., 2 (1994), 173.
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Decomposition of CH4 gas by arc discharge Mass spectroscopy of CH4 gas before and after arc discharge Thermal decomposition of CH4 ambient gas ２ CH4 C２H２ + ３ H２ (2 mol → 4 mol) Gas pressure ratio after and before evaporation： Eva. in He gas ---1.05 times Eva. in CH4 gas --- 2.0 times
Similar results were obtained in C2H2 and CH4 ambient gases What is the result of pure H２ gas as ambience? M. Wang et al.: Fuller. Sci. & Tech., 4 (1996), 1027.
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Arc evaporation of pure graphite in pure H2 ambience Optical photo of the top of the cathode
MWNTs
Carbon Roses : Graphene
Y.Ando, X.Zhao & M.Ohkohchi, Carbon, 35 (1997), 153. X. Zhao et al.: Carbon, 35 (1997), 775.
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HR-SEM before and after purification
Before purification Arrows: nanoparticles
After purification 17
HR-TEM micrograph of H2-arc MWNT
Regular spacing of 3.4 Å Oxidation starts from tip of MWNT Thin innermost tube, 11Å 18
3Å diameter innermost tube
X. Zhao, Y. Ando et al., Phys. Rev. Lett., 92 (2004), 125502.
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1D Quantum Confinement Effect Observed in Raman Spectra
G-band D-band
RBM peaks
(a) Low frequency region
(b) High frequency region
MWNTs ：Multi-walled carbon nanotubes HOPG: Highly oriented pyrolytic graphite SWNTs：Single wall carbon nanotubes prepared by APJ method
X. Zhao, Y. Ando, L-C. Qin, H. Kataura, Y. Maniwa, R. Saito: Physica B 323 (2002), 265. Chem. Phys. Lett. 361(2002), 169. Appl. Phys. Lett. 81 (2002), 2550.
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Intensity (arb. unit)
New Raman peak for H2-arc and D2-arc MWNTs
new Raman peak
G-band
514.5 nm
D-band
Raman Shift (cm-1)
M. Jinno, S. Bandow, Y. Ando; Chem. Phys. Lett., 398 (2004), 256.
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Carbon Nanowire : Carbon Chain in MWNT
X. Zhao, Y. Ando, Y. Liu, M. Jinno, T. Suzuki: Phys. Rev. Lett. 90 (2003), 187401. 22
Production of Single Wall Carbon Nanotubes (SWNTs) by Arc Discharge
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Essential difference between MWNTs and SWNTs production by DC arc discharge MWNTs
SWNTs
Electrode
Pure graphite rod
Graphite rod including metal catalysts
Produced place
Cathode deposit
Web in chamber 24
Production of SWNTs by arc discharge method Arc discharge of graphite rod including metal catalysts ◎ Arc Plasma Jet (APJ) method 4%Ni-1%Y catalyst, He 500Torr ambient gas Inclined electrodes, 30°
; Yield: 1g / min
◎ conventional DC-arc discharge method (FH-arc method) single Fe catalyst, H2-Ar 200Torr mixed gas → macroscopic SWNTs web longer than 30cm ◎ conventional AC-arc discharge method (by Ohkohchi) two electrodes including different metal catalysts 25
SWNTs Produced by Arc Plasma Jet (APJ) Method APJ method
Usual method
Production rates of SWNT soot (a) APJ
(b) Normal arc
Apparatus of APJ method Y. Ando et al.:Chem.Phys. Lett., 323 (2000), 580. SEM & TEM images of SWNTs prepared by APJ method
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FH-arc Method Usual DC Arc Evaporation： Atmospheric Gas; gas H H22-Ar -Armixture (1:1) mixture gas [Total Pressure 200 Torr] Anode; 1.0 at% Fe graphite rod Cathode; Pure graphite rod Evaporation time; 5 min
Huge web of SWNTs
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Macroscopic SWNT web produced by FH-arc Photo of macroscopic SWNT web ～30cm
SWNTs bottled in one liter bottle Mass is only 1g 28
SWNTs Web Like Lace Curtain
1 cm
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Optical Photograph of Huge SWNT Web
Mass of this huge SWNT web is only ～20 mg
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Electron micrographs of macroscopic SWNTs web
31 As grown: (a) TEM, (b) HR-TEM
Purified: (c) SEM, (d) TEM
X. Zhao, S. Inoue, M. Jinno, T. Suzuki, Y. Ando: Chem. Phys. Lett. 373 (2003), 266.
Purification of SWNTs Heat Treatment
Heat Treatment HCl Treatment Ultrasonic Cleaning Centrifuge Drying Characterization
HCl Treatment 32
(EDX) Heat + HCｌ
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CNT Growth from Camphor by CVD Method
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Camphor (C10H16O)
C H O
White crystalline solid Melting Point: 180℃ Cinnamomum camphora Boiling Point: 210℃ Camphor (96%) Price: 1000 ¥/kg
Why Camphor ? 1.
High abundance (cheap material): Economy-friendly
2.
Green plant product: Ecology-friendly
3.
Non-toxic: User-friendly
4.
It contains both hexagonal and pentagonal carbon rings.
5.
Its oxygen helps oxidizing amorphous carbon in-situ.
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Mass Production of CNTs from camphor Zeolite as a catalyst support
Iron and cobalt catalyst in the zeolite pores
After CVD at 650˚C
CNTs from zeolite pores
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CNT growth using zeolite support
Carbon 43 (2005) 533-540
► Vaporisation of bare camphor over Fe-Co-impregnated zeolite support gives both SWNTs and MWNTs. ►SWNTs are found in a temperature range of 850–950˚C. Highest yield is ~30% (relative to the support material) at 900˚C. ►MWNTs are obtained in a temperature range of 550–950˚C. Highest yield is ~1000% (relative to the support material) at 650˚C.
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MWNTs as a function of growth temperature 600℃
550℃
20 nm
20 nm
700℃
120 nm
800℃
120 nm
Carbon 43 (2005) 533-540
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Gigas Growth of CNTs Zeolite bed before CVD 1.2g
Heat 650˚C
0.6g
Zeolite bed after CVD 6.6g
Gigas Growth
Weight gain = 1000% Volume gain = 10,000% 6g CNTs from 12g camphor (30-min CVD) A breakthrough in the utmost utilization of a carbon source for CNT growth.
NT07 Brazil
C10H16O Conventional CNT sources
Methane: CH4 Ethylene: C2H4 Acetylene: C2H2 Benzene: C6H6
• • • •
Camphor Carbon-rich Hydrogen-rich Oxygen-present
Utmost atomic utilization !!! CNT yield w.r.t. camphor feed = 50 wt% CNT yield w.r.t. the source carbon = 61 wt% CNT yield w.r.t. camphor can go up to ~80% 40
Industry-level Production of MWCNTs Using Rotary Kiln Setup
camphor
zeolite
MWCNTs 10 kg/day (as-grown purity = 90%)
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Camphor CVD Today 300g CNTs/hour using rotary kiln
• Meijo University • Meijo Nano Carbon Co. Ltd. • Takasago Industry Co. Ltd. • Masuoka Ceramic Materials Co. Ltd.
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APPLICATIONS OF CNTs Field emission from vertically aligned CNTs Turn‐on field for 10 µA/cm2 = 0.6 V/µm Threshold field for 10mA/cm2 = 3 V/µm
Flexible Transparent CNT‐Epoxy Films 0.5% CNT in PVA Sheet Resistance = 3.8 kΩ/□
Expected Applications
CNT‐based Solar Cell Proposal h e-
• Telecommunication • Transportation • Computing and Data Storage • Materials and Manufacturing
• Energy and Environment
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Thank you very much!!
