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
Thread
2-Ply Yarn
Nano Volleyball Net
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?
Top View
Cross-Section
80nm imprinted depth
170nm resist layer
substrate
40nm
Nano-Thread
(800 nm diameter)
Robot with Rotation
Tool for Spinning
Nano-Thread
(300 nm diameter)
Thread (20 micron diameter)
with a thin polymer coating
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=3d+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)
(b)
(c)
(d)
0.1mm
1mm

49
Fj ( BLayj ) 
i 1
Figure 5. Solenoid magnetic force.
1mm
I 2 (a  ( j  1)d )6 
4
3
iL 2

 iL 2

)  (a  ( j  1)d ) 2   (
)  (a  ( j  1)d ) 2 
( L 
N 1


 N 1


3





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.
Improving the electrical conduction of CNTs
•
Possible approaches: 1-Improve CNT quality, 2-All metallic CNT, 3Dense CNT, 4-Doping.
Consider dense CNT operating at high temperature:
The Acnt and Acs in a MWCNT are:

N
RAcnt
L
Acs; Cross Sectional
Area of CNT
N
Acnt
 t
N
D ;
i
Di  Do  i  12t 
i 1
DWCNT
Five Wall CNT
Acnt; Area of CNT
ends for conduction
Manufacturing Long Carbon Nanotubes
•
Horizontal growth
Manufacturing Long Carbon Nanotubes
T
B
Catalyst Agglomeration
Manufacturing Long Carbon Nanotubes
Approaches to Telescope Nanotubes
1. Mechanical: MWCNT
telescoped using AFM tip
(by Alex Zettl)
+
+
+
-
Epoxy
p
2. Electrical: MWCNT
telescoped using electrical
charge repulsion/attraction
Iron
3. Hydraulic/pneumatic: MWCNT
telescoped using pressure (outer
tubes opened at ends, inner tubes
closed)
Telescoping Nanotube Array with Feedback Control
Wave Sensor to Measure Freq. and Compute λ/2
Flexible Skin
Telescoping
Nanotube
Array
Feedback Control System
λ/2-lo
+
G
Kp
-
V
Kv
Lcnt
Active Material Surface
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
Medium Panels
Thin Panels
Gas
flow
Thick Panels
Gas flow between
panels increases
the growth rate
Centimeter
height
Posts of Nanotubes
Forms of Nanotubes
Experiments to Control the Geometry of Nanotube
Arrays
Summary and Conclusions
• 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
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