Development of a Carbon Nanotube Stripper Foil

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Development of a Carbon Nanotube Stripper Foil

• Karl von Reden and Enid Sichel
• Geology and Geophysics Department

Presented at the Symposium of Northeastern
Accelerator Personnel 2003, Strasbourg, FR
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Outline

• Introduction reasons for doing this
• State of the art in nanotube RD
• Problems
• Our progress (so far)
• What is next?

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Reasons for doing this
Compact Accelerator Mass Spectrometry systems
with accelerating voltages lt 500 kV are under
development. Stripper thickness needed 2 5
mg/cm2
Gas stripping requires large effort in vacuum
pumping to reduce background from scattering
outside of the stripper canal
Characteristics of nanotubes and their (purified)
aggregates might be superior to traditional
amorphous, graphite, even diamond-like films
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State of the art in nanotube RD
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SWNT ropes (from R. Smalleys group)
Thess et al., 1996
Rinzler et al., 1998
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M. Daenen et al., 2003
Who
How
Typ. Yield
SWNT
MWNT
PRO
CON
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Properties of single-walled carbon nanotubes
(SWNT)and other forms of carbon
SWNT Diamond Graphite
Average diameter (nm) 1.3 Length/diameter
ratio 1000 Density (g/cm3) 1.35
3.5 1.8 Band gap (eV) 5.5 0.0 metallic
SWNT 0.0 semiconducting SWNT 0.5 Resistivity
(Wcm) 10- 4 1016 10- 3 Max. Current Density
(A/m2) 1013 N/A Thermal Conductivity
(kW/m/K) 2 2 0.08-0.25 Youngs Modulus
(Tpa) 1 0.01 Max. Tensile Strength
(Gpa) 100 100 0.05
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Problems?
Homogeneity (pin holes, clusters) Required
condition Beam spot large compared to nano
structure Constant average foil thickness (no
taper or other macroscopic changes across the
foil)
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Thickness variability of foils(from AFM images)
AD foil
DLC foil
Liechtenstein et al. 1999
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Graphite foils
Jeschke et al., 2001
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Progress (so far)
Collaborations or contacts started with

• Doug Chrisey, NRL MAPLE Facility
• Gary Wnek, VCU Electro-spinning Facility
• Frank Hennrich, Uni. Karlsruhe, FZK
• Commercial Suppliers
• Testing possible at Paul Skippers
  biomedical AMS Facility at MIT
• or at the NRL TEAMS Laboratory

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MAPLE
Pique, McGill, Chrisey, 2000
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Electro-spinning
D. Li et al. (UW), 2003
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DC glow discharge, RF glow discharge
Liechtenstein et al., 1997
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Laser plasma ablation deposition
Maier-Komor, 1995
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Laser ablation
Lebedkin et al., FZK (2001)
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Hennrich et al. 2002
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Hennrich - 2
Hennrich et al. 2002
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Commercial SWNT films
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What is next?

• Try out Karlsruhe type film in one of the AMS
  labs with accessible terminals
• Follow SWNT RD (mats of highly
  aligned few-mm-long SWNT ropes desirable)
• Consider other structures Stripper canals
  filled with nano wool?

This work is supported by a grant from WHOIs
Cecil H. Ida M. Green Technology Innovation
Awards