These slides use concepts from my (Jeff Funk) course entitled analyzing hi-tech opportunities to analyze improvements in the economic feasibility of carbon nanotubes (CNTs) for transparent electrodes and flywheels. Improvements in the transparency and cost of CNTs are enabling CNTs to replace indium tin oxide in applications such as solar cells and displays. Second, as the cost of CNTs falls through improvements in processes and increases in the scale of equipment, they will become economically feasible for flywheels. Since the energy storage density of flywheels is directly proportional to the strength to weight ration of the flywheel material, CNTs (and graphene) have potential energy storage densities that are ten times the current energy storage densities of carbon fiber-based flywheels and Li-ion batteries. This means that carbon nanotubes are an important tool in the battle against fossil-fuel dependency and global warming.

1. Carbon Nanotubes
Flywheels & Transparent Electrodes
HASSANALI GHAEDAMINI HAROUNI - A0068990M
LO KWOK WAH DENNIS - A0005859X
LOW GUAT SIM - A0082071N
GOPALAKRISHNAN NANDINI - A0098547L
RAGUNATH GUHA - A0082085E
SHEN ZIHONG - A0046147H

2. Outline
Background of CNT
 What are they?
 Synthesis & Properties
 Emerging Applications
 Growth Drivers
 Market Demand
 Prices of CNT
 How cheaper can CNT get?
 Entrepreneurial Opportunities
 Transparent Electrodes &
Flywheels
 Challenges & Improvements
 Conclusion
 Q &A


3. CNT - What are they?
A graphite sheet rolled into a seamless cylinder




Multi-walled (MWCNT): Concentric or spiral
Single-walled (SWCNT): Zig-zag, armchair or chiral
Fullerite: Polymerised single walled
Torus: Nanotube bent into doughnut shape
E.T.Thostenson et al. / Composites Science and Technology (2001)

4. CNT - Synthesis
Carbon Nanotubes can be synthesised in 3 main ways
 Arc Discharge
 Laser Ablation
 Chemical Vapour Deposition (CVD)
Other techniques are:
Flame pyrolysis, Bottom-up organic approach,
High-Pressure CO Conversion (HiPco),
Thermal Plasma Synthesis, Rotation Reactors
(Improved CVD), CCVD (Catalytic CVD).

5. CNT - Properties
Among the other properties of CNT, the most prominent ones are :
Electrical
Mechanical
Field emission in vacuum electronics
Building block for next generation of
VLSI*
Nano lithography
Has constant resistivity & a tolerance
for very high current density
Armchair structures are metallic while,
chiral can be a moderate
semiconductor
Diamond
CNT
Steel
Youngs
Modulus(GPa)
1220
1000
210
Tensile
strength(GPa)
1.2
63
1.2
Yield stress(GPa)
16.53
52.00
0.83
Density(g cm-3)
3.52
1.35
8
Thermal
Good thermal capacitors along tube &
insulators laterally to the tube axis.
15 times more heat conductive than copper
Temperature stability -up to 2800oC in vacuum
& about 750oC in air
*Very
Large Scale Integration

6. Emerging Applications
The unique electrical and mechanical properties of CNT has
been modified to assemble them into devices like:
 Flywheels for
Uninterrupted Power
Supply (UPS)
 Transparent electrodes
 Lithium-ion batteries
 Super-capacitors
 CNT-based electronic
components such as fieldeffect transistors (FETs).

7. Market Demand of CNT
Electronics & Data Storage
Energy
Source: http://www.electronics.ca/presscenter/articles/1204/1/Market-Applications-of-Carbon-Nanotubes/

8. Prices of Materials (Multi-tonnes)
10.000
1.000
SWNT (90wt%)
Indium
Silicon
MWNT
Carbon Fibre
0.010
Steel
0.001
Year
Source: Multi-source (please refer to the comments section)
2016
2015
2014
2013
2012
2011
2010
2009
2008
2007
2006
2005
2004
2003
2002
2001
2000
1999
1998
1997
1996
0.000
1995
Price (USD/gram)
0.100

9. Price at various purity levels (2013)
Price of CNT
80.0
70.0
60.0
($'000)
50.0
99% SWCNT
90% SWCNT
40.0
60% SWCNT
30.0
99% MWCNT
95% MWCNT
20.0
10.0
0.0
1
10
25
50
100
500
1000
Weight (g)
Source: http://www.cheaptubesinc.com/carbon-nanotubes-prices.htm#Single_Walled_Nanotubes_Prices

10. How much cheaper can CNT get ?

11. CNT Cost vs Production capacity
Source: www.small-journal.com reviews © 2013 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
The Road for Nanomaterials Industry: A Review of Carbon Nanotube Production, Post-Treatment and Bulk Applications for
Composites and Energy Storage

12. Production Capacity vs Actual Production
14000
CNT Production (tonne)
12000
10000
8000
6000
4000
2000
0
Spare capacity (tonne)
Actual Production
(tonne)
Yr 2008
656
Yr 2009
1690
Yr 2010
3355
Yr 2015
3000
340
500
710
9300
Source: http://www.prnewswire.com/news-releases/production-and-application-of-carbon-nanotubes-carbon-nanofibers-fullerenesgraphene-and-nanodiamonds-a-global-technology-survey-and-market-analysis-131970098.html

13. Manufacturing process of CNT
Process/ Source
Carbon Fibre
CNT
Precursors
Polymer (polyacrylonitrile,
polyethylene)
Carbon containing gas
(methane, ethane etc) +
metal catalyst (Ni etc)
Synthesizing
Oxidation and carbonization
Carbonization (breaking off
carbon)
Surface treatment
Liquid Oxidation with acid/
alkaline
Acid washing
Spooling
Sheets,Vertically aligned, etc
Packaging

14. Manufacturing cost of CNT
Source: Rocky Mountain Institute, 2011

15. Using Waste material (as precursors) for
CNT Production
Reasons:
 Availability of large volume of waste produced worldwide
composed of polymers (polyethyelene, polypropylene etc)
 Plastic polymers serve very well as carbonaceous feed for CNT
production
 Energy and resource intensive production of CNTs
More cost efficient as, precusors are the main contributor to
high-cost
Source: Chemical Engineering Journal 195–196 (2012) 377–391

16. Materials as precursors for Production of
VA-CNT
Source: Towards large scale aligned carbon nanotube composites: an industrial safe-by-design and sustainable approach: Journal of
Physics: Conference Series 429 (2013) 012050

17. Alternate energy to lower Mfg cost
Source: Renewable and Sustainability Reviews, Volume 22, June 2013, Pg 560-570

18. Carbon Nanotubes in
Transparent Electrode &
Flywheels

19. Transparent Electrode
What is transparent electrode?
 A transparent and conductive material
 For devices like touch screens, LCDs, OLEDs, Solar cells
Transparent electrodes to be used in display
panels:
 Higher conductivity
 Higher transparency

20. Indium Tin Oxide (ITO) in Transparent
Electrodes
Advantage
Disadvantage
Ease of fabrication
Expensive and time-consuming multi stage
refining process with low efficiency (15 to 30%)
Consistency and
reproducibility
Shortage of supply: Indium is a by product of
other mining operation, eg. Zinc and Lead
Mature technology
Increasing cost of ITO
Good transmittance in the
visible (>80%) and near IR
regions
Low resilience to mechanical stresses
Low electrical resistivity
Inherently brittle in nature
Flexible substrate, deterioration in the
conductivity when subjected to thermal and
mechanical strains
Degrade with time when subjected to
mechanical stress

21. Alternative materials in Transparent
Electrode
Carbon Nanotube
(CNT) films
B) Random Net works of
metallic nanowires
C) Metal gratings
D) Graphene films
A)
Source: Kumar, Akshay, and Chongwu Zhou. "The race to replace tin-doped indium oxide: which material will
win?." ACS nano 4.1 (2010): 11-14.

22. Carbon Nanotubes for Transparent
Electrodes
Optoelectronic property of CNT network films
 ITO performance (100 Ohm/sq and >90% transparency)
 Unidym CVD nanotubes outperforms any other CVD
tubes together with Laser and Arc tubes
Source: Park,Young‐Bae, et al. "37.4: Late‐News Paper: Integration of Carbon Nanotube Transparent Electrodes into Display
Applications." SID Symposium Digest of Technical Papers. Vol. 39. No. 1. Blackwell Publishing Ltd, 2008.

23. Hybrids of CNT network films
Price
CNT
Conductivity
Transparency
Flexibility
√
ITO
√
√
√
 Contact resistances and semi-conducting nanotubes of
the nanotube network films
 Chemical doping
 Hybridization of conducting guest components
o Acid treatment
o Deposition of metal nanoparticles
o Creation of a composite of conducting polymers
 Surface-modified carbon nanotube networks for
transparent conducting film applications

24. Result of Chemical Doping
One tenth
reduction in
resistance by
post treatment
of CNT
Source:Yang, Seung Bo, et al. "Recent advances in hybrids of carbon nanotube network films and nanomaterials for
their potential applications as transparent conducting films." Nanoscale 3.4 (2011): 1361-1373.

25. Flywheels
What are Flywheel Energy Storage Systems?
Consists of 3 major components:

Flywheel (Rotor, Rotor’s bearing & Housing)

Electrical motor/generator to transfer electricity

Controlled electronics for connection to a larger
electric power system
Basic Operating Principle of Flywheel Energy Storage System:
Source: www.youtube.com/watch?v=u6I2lKtfpLQ

26. Why Flywheels for Energy Storage?
ESS Feature
Lead Acid Battery
Flywheel Battery
Chemical
Mechanical
Energy Density
Higher
Lower
Power Density
Lower
Higher
75%
95%
Storage Mechanism
Efficiency (input/output)
Flywheel
$50 -$100 (USD)
CNT
$400 - $800 (USD)
Higher
Lower
3-5 yrs
> 20 yrs
Charging Capabilities
Slow
Rapid
Charging Cycles
1000
100,000
Proven
Promising
Disposal Issues
Slight
Temperature Range
Limited
Less Limited
Relative Size (equivalent power/energy)
Larger
Smaller
Annual Sales ($Millions USD)
~ 7000
~2
Price per Kilowatt
Maintenance
Operating Life
Flywheel
CNT
Technology
Environmental Concerns
Source: http://www.globalrenewablenews.com/?

27. Design for Flywheels
Mass (m) x 2
Energy (Ek) x 2
Velocity (v) x 2
Energy (Ek) x 22
Increasing Mass of Rotor
Increasing Velocity of Rotor
Slow Speed Flywheels
High Speed Flywheels
Store twice as much energy when it
spins at the same speed
Store quadruple as much energy when it
spins twice the speed
Dense and Large (Larger Footprint)
Lighter and Smaller (Smaller Footprint)
Deliver a large amount of power for a
short period of time
Produce usable work or electrical energy
for hours but in smaller quantities
Applications: Emergency backup
power sources
Applications: Motor vehicles
Source: http://cdn.intechweb.org/pdfs/20363.pdf

28. Limitations for High
Speed Flywheels
 Current Materials Used For Rotors: Steel or Carbon Fiber
 As Speed of rotor increases, the energy stored is limited by the
strength of the rotor material
 Rotor eventually reaches a point where the force is too great
that it shatters into fragments

29. Carbon Nanotubes for High Speed
Flywheels
Specific tensile
strength of the
material
Specific Density (ρ)
T. Strength (σt)
Carbon Nanotubes are 10 times much stronger than Carbon Fiber
& 20 times much stronger than Steel
Source: http://cdn.intechweb.org/pdfs/20363.pdf

30. Challenges for High Speed Flywheels
Year
Carbon Fiber
Carbon Nanotubes
2016
$0.018
$0.16
2015
$0.022
$0.18
2014
$0.027
$0.20
2013
$0.031
$0.23
*Price (USD/gram)
Cost approximately 9
times that of Carbon Fiber
Solution:
 Drive CNT prices down through Mass Production
 Use of existing manufacturing process
 Use of renewable resources for manufacturing (Materials & Energy)
Source: Multi-source (please refer to the comments section)

31. New Industry/ Product Opportunities for
Carbon Nanotubes
Energy
Electronics
Silicon replacement semi conductor circuit
Solar heat electric generation
Power semiconductor heat dissipater
Power cables
Aircraft body fortifying material
High electric conductivity rubber roller
Wind power generator fan blade
High temperature range visco-elasticity
High Functionality Materials
Structural Materials

32. Challenges:
1. High Cost of CNT
2. Manufacturing CNT to create new and different
structural and functional properties suitable for
different applications
Solutions:
1. Driving down CNT prices through mass production
2. Exploit existing manufacturing process (e.g.: CVD)
3. Use of renewable resources (material & energy) to
reduce manufacturing cost
Once these challenges are overcome, the growth in
global CNTs demand is expected to accelerate
thereafter. Based on the trend analysis, our team
projects that Carbon Nanotubes would become
feasible, around 25 years from now for majority of the
applications

33. T
H
A
N
K
T
H
A
N
K
Y
O
U
Y
O
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