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Carbon Nanotube Materials A Family of Forms
Vesselin Shanov, Chaminda Jayasinghe, Wondong Cho, Rajiv Venkatasubraman, Rutvij Kotecha, David Mast, Mark Haase, Noe Alvarez, Pravahan Salunke, Anshuman Sowani,
Weifeng Li, Brad Ruff, Ge Li, Arvind Krishnaswamy, Doug Hurd, Larry Schartman, Mark J. Schulz
UC NANOWORLD Laboratories
University of Cincinnati, Cincinnati, OH www.min.uc.edu/nanoworldsmart
October 24, 2012
Materials Processing – Molecules to Materials Nanotube Materials
Forest or array
Winding ribbon
Ribbon
Yarn Nano Volleyball Net
Thread 2-Ply Yarn
Patterning Nanotube Arrays
• High performance applications (optics, telescoping, long CNT,
spinable CNT, devices, 3-D Arrays, others) will eventually require
patterning CNT
• Our approach to pattern arrays: NIL
• Potential to control catalyst position, and size, nanotube size,
diameter, number of walls, length, collimation, maybe chirality?
170nm resist layer 80nm imprinted depth
substrate
Cross-Section Top View
40nm
Robot with Rotation Tool for Spinning
Thread (20 micron diameter) with a thin polymer coating
Nano-Thread (800 nm diameter)
Nano-Thread (300 nm diameter)
Ni Nanowires at Different Magnifications
Iron Nanotubes
magnetite (Fe3O4), Vijay Varadan, U. Arkansas
Why do carbon nanomaterials have such extreme properties?
1. CNT shells are one atomic layer thick, which means their density is low
2. The strong triple sp2 bonding of carbon combined with the hexagonal tessellated
architecture of nanotubes provides high strength
3. The hexagon structure is the highest order polygon that tessellates and can
be considered as a fundamental platform from which to design new atomic
layer compounds and hybrid inorganic materials with 1, 2 or 3-D
dimensionality
Tessellation: Tiling a floor with shapes that do not overlap or have gaps.
a tessellation of triangles
a tessellation of squares
a tessellation of hexagons
http://www.google.co.uk/search?q=3-
d+tessellation&hl=en&prmd=imvns&tbm=isch&tbo=u&source=univ&sa=X&ei=UcNGT
722NY2XhQeS2oywDg&ved=0CFEQsAQ&biw=1600&bih=882
Developing a Pilot Microfactory to Build Nanorobot Devices
•To build small mechanical and electrical parts and micro-devices •Robot tools grip, apply force, twist, measure and build smaller robots, and they build then smaller robots (collaborating with Dr. Krzysztof Koziol)
Kleindiek Robot tools
CNT Thread for Carbon Electric Motors & Devices
(a)
Carbon electromagnetics: (a) whirling CNT yarn, the first demonstration of the
principle of a carbon electric motor; (b) high current density of CNT yarn; (c)
high electromagnetism of CNT yarn coil; (d) coil force.
Figure 5. Solenoid magnetic force.
1mm 1mm
0.1mm
3
22
3
22
49
1
62
))1(()1
())1(()1
(4
))1(()( dja
N
iLdja
N
iLL
djaIBF
i
Layjj
(b) (c)
(d)
Improving the electrical conduction of CNTs
• Possible approaches: 1-Improve CNT quality, 2-All metallic CNT, 3-
Dense CNT, 4-Doping.
Consider dense CNT operating at high temperature:
The Acnt and Acs in a MWCNT are:
Acs; Cross Sectional
Area of CNT Five Wall CNT
L
RANcnt
tiDDDtA oi
N
i
iNcnt 21;
1
DWCNT Acnt; Area of CNT
ends for conduction
Manufacturing Long Carbon Nanotubes • Horizontal growth
Manufacturing Long Carbon Nanotubes
Catalyst Agglomeration
T
B
Manufacturing Long Carbon Nanotubes
1. Mechanical: MWCNT
telescoped using AFM tip
(by Alex Zettl)
Approaches to Telescope Nanotubes
3. Hydraulic/pneumatic: MWCNT
telescoped using pressure (outer
tubes opened at ends, inner tubes
closed)
2. Electrical: MWCNT
telescoped using electrical
charge repulsion/attraction
- +
+ +
p
Epoxy Iron
Telescoping Nanotube Array with Feedback Control
Kp λ/2-lo + -
G
Lcnt
Feedback Control System
Telescoping
Nanotube
Array
Active Material Surface
Wave Sensor to Measure Freq. and Compute λ/2
Flexible Skin
Kv
V
A CNT Array that can be spun into yarn
UC Spinning machine (built by Mr. Doug Hurd, Dr. Nilanjan Mallik)
Spinning from a wafer
Ref. R.H. Baughman,
C. Cui, A.A. Zakhidov,
Z. Iqbal, J.N. Barisci,
G.M. Spinks, G.G.
Wallace, A. Mazzoldi,
D. DeRossi, A.G.
Rinzler, O. Jaschinski,
S. Roth, M. Kertesz,
Science 284 (1999).
Long CNT tiles that cannot be spun into yarn using the
existing spinning machine
• CNT Panels grown using a mask or NIL
• 1.5 cm height, 5 cm width, thickness 50 nm - mm
Gas flow between
panels increases
the growth rate
Centimeter
height
Gas
flow
Thin Panels
Thick Panels
Medium Panels
Posts of Nanotubes
Forms of Nanotubes
Experiments to Control the Geometry of Nanotube
Arrays
• A family of forms of nanotube materials is being developed
• When the fundamental technology for synthesis is optimized the
technology will be turned over to industry for scale up
Summary and Conclusions
Sponsors
• NSF ERC for Revolutionizing Metallic Biomaterials (EEC-0812348),
Program Officer Dr. Leon Esterowitz
• NSF SNM GOALI: Carbon Nanotube Superfiber to Revolutionize
Engineering Designs (1120382), Program Officers Dr. Bruce Kramer,
Dr. Grace Wang
• Any opinions, findings, and conclusions or recommendations
expressed in this material are those of the authors and do not
necessarily reflect the views of the National Science Foundation
• Office of Naval Research, Program Officer Dr. Ignacio Perez
• General Nano LLC, President Mr. Joe Sprengard
• University of Cincinnati
Collaborators, Affiliates
• Atkins & Pearce
• Parker Hannifin
• Boeing
• General Nano
• Interstellar Technologies
• Innovent Scientific Solutions
• Odysseus Technologies