Project #4 Manufacture and
Characterization of Carbon Nanotube
Microcable
Sponsored By The National Science Foundation
Grant ID No.: DUE-0756921
Timothy Ochmann(Pre-Junior ChE) & Nicholas Kienzle(Pre-Junior ChE)
Faculty Mentors: Dr. Vesselin Shanov & Dr. Noe Alvarez SEEMBE
College of Engineering and Applied Science; University of Cincinnati; Cincinnati, Ohio
04.04.13 3:30 P.M.
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Outline
•
•
•
•
Background
Goals
Process
Results
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Discovery
Russia 19521
1. .LV Radushkevich and VM Lukyanovich. "The structure of the carbon produced by the thermal
decomposition of carbon monoxide on iron contact." ЖФХ, 26, 88 (1952))
2. Iijima, S., “Helical microtubules of graphitic carbon”,. Nature 354, 56 - 58 (1991)
Japan 19912
3
Background Cont.
Figure : Singlewall Carbon Nanotube vs. Multiwall Carbon Nanotube3
3. http://people.bath.ac.uk/tl258/Types.html
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Background Cont.
• As Spun CNT Thread –
Conductivity of 3.8 * 104 S/m
• Future use in Power
Distribution
• High Cycle Fatigue,
Corrosion Resistant
5
Background – Band Gap
• Gap between Conduction
Band and Valence band
• Attempting to “close” the gap
using various chemicals
• Determines Electrical
Properties of material
• Exohedral Doping to solve
problem
Coating
CNT thread
Metals
2.http://www2.warwick.ac.uk/fac/sci/phttp://www2.warwick.ac.uk/fac/
sci/physics/current/postgraduate/regs/mpags/ex5/bandstructure/hysi
cs/current/postgraduate/regs/mpags/ex5/bandstructure/
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Project Goals
• Increase Conductivity of CNT thread
• Coat CNT thread for insulation
• Create demonstration for enhanced CNT thread properties as an
electrical wire
• Fully characterize CNT thread (mech. strength, electrical, Raman
spectroscopy)
NOTE: work is towards continuing progress in electrical and
strength improvements for use as a super fiber in future
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Chemical Vapor Deposition
Note:
Using Si
substrate
Figure 3: Schematic of CVD system4
C2H4 (g) in Ar(g) carrier gas
4. Ge Li, Supriya Chakrabarti, Mark Schulz, Vesselin Shanov, Carbon, Volume 48, Issue 7, June 2010,
Pages 2111-2115, ISSN 0008-6223, 10.1016/j.carbon.2010.01.054.
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Dry Spinning CNT Array into CNT
Thread
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Dry Spinning at UC Nanoworld
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Scanning Electron Microscope
(SEM)- As spun CNT Thread
Figure 8: SEM image of CNT thread as spun.
Image taken 08.30.12.
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Doping Method
• Liquid phase doping
• Stand holds bobbin
• CNT thread is drawn
from solution for drying
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Post Treatment Agents
Dopants
• Nitric Acid
• Potassium
Tetrachloroaurate (III)
Solvents
• Acetone
• DMSO
• N-methyl-pyrrolidone
Exohedral Doping
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SEM Image – Acetone Densified
CNT Thread
Figure 9: SEM image of CNT thread with post processing.
Image taken 08.30.12.
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SEM Image – Au/HNO3 Doped CNT
Thread
Figure 10: SEM image of CNT thread after Au/Nitric Acid Doping5
5. Noe Alvarez, Ruff, Haase, Malik, Kienzle, Mast, Schulz, Shanov,
Recent Advances in Circuits, Communications and Signal Processing
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Polymer Coating for Wire Insulation
Collecting
bobbin
Hydrogenated Nitrile Butadiene Rubber
Dissolved in Butyrate Thinner from Randolph
Aircraft Finisher with cross linking agent
LUPEROX ® 101
Heater
Polymer
Bath
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SEM Image – Nitrile Polymer Coated
CNT Thread
Figure 11: SEM image of CNT thread after Hydrogenated Nitrile Butadiene Rubber Coating5
5. Noe Alvarez, Ruff, Haase, Malik, Kienzle, Mast, Schulz, Shanov,
Recent Advances in Circuits, Communications and Signal Processing
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Characterization – 4 Point Probe
Resistance Test
𝜌=
𝑅𝜋𝐷2
4𝐿
• Silver paint was used to
attach the CNT thread to the
pins.
V = Voltage
I = current
supplied
Figure 11: 5 pin connector used as a template
for 4 point probe resistance test (test length of
4.2 mm with silver paste connections
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Tensile Strength Improvement
Stress vs. Strain comparison
• Ultimate Tensile
Strength Improves
• Elastic Modulus
Improves
(Stress/Strain)
• Toughness improves
AP71
Reference
AP71 Au
Doped
Au Doped
As Spun
300
250
Average
Ultimate
Stress (MPa)
Average
Average
Moduli (GPa)
Toughness
(MPa)
115.56
4.7093
2.3416
338.55
23.808
4.2526
Stress in MPa
CNT Thread
Name
350
200
150
100
50
0
-50
0
0.01
0.02
Strain
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0.03
0.04
Raman Spectroscopy
• D Peak – presence of sp2
hybridized
• G Peak – Graphitic peak
• G’ Peak – second vibrational
mode of CNT
• D:G Ratio – measure of
amorphous carbon on surface
as well as other defects
G Peak
G’ Peak
D Peak
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Raman Spectroscopy - Coated
• Spectrum for HNBR
1
• Spectrum for HNBR Coated
2
2
6. K.D.O. Jackson, M.J.R. Loadman, C.H. Jones, G. Ellis, Fourier transform raman spectroscopy of elastomers: An
overview, Spectrochimica Acta Part A: Molecular Spectroscopy, Volume 46, Issue 2, 1990, Pages 217-226, ISSN
0584-8539, 10.1016/0584-8539(90)80091-C.
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1
Application - Microcable
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Conclusion
Properties
Au Doped CNT
Thread
Literature6
Copper
Conductivity
(S/m)
1.37*105
6.67*106
5.96*107
Density
(g/cm^3)
~1.0
~1.0
8.96
6. Yao Zhao,Jinquan Wei1, Robert Vajtai, Pulickel M. Ajayan, and Enrique V. Barrera
“Iodine doped carbon nanotube cables exceeding specific electrical conductivity of metals”,
Nature, September 2011
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Acknowledgements
• Dr. Vesselin Shanov and Dr. Mark Schulz (lab
directors of Nanoworld Labs)
• Dr. Noe Alvarez and Dr. Weifeng Li (post doctorates)
• Mark Haase, Rachit Malik, Joe Sullivan, Adam Hehr,
Brad Ruff (graduate students)
• Doug Hurd (machine shop director)
• National Science Foundation for funding our work
• General Nano LLC (facilities for catalyst preparation)
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