This document discusses carbon nanotubes and their potential uses. It describes how carbon nanotubes are synthesized using chemical vapor deposition and other methods. It also discusses challenges in purifying and functionalizing carbon nanotubes. Potential applications mentioned include using carbon nanotubes for energy conduction, energy storage, new composites and fibers. Some current real-life uses discussed are using carbon nanotubes to strengthen composites and provide protection and insulation in aircraft.

1. Nanomaterials ReviewNanomaterials Review
Last Time onLast Time on The Wide World of NanoThe Wide World of Nano ……

What are nanoparticles, nanomaterials, and what’s out there?What are nanoparticles, nanomaterials, and what’s out there?

How do we analyze and control production of such small things?How do we analyze and control production of such small things?

What detection methods do we have and how good are they?What detection methods do we have and how good are they?

Where does your company fit in? => in most cases, it’s on theWhere does your company fit in? => in most cases, it’s on the
Integration side; not Production.Integration side; not Production.
(image taken from
http://www.nature.com/nnano/journal/v4/n1/fig_tab/nnano.2008.36
4_F1.html)
(image taken from
http://www.laboratoryequipment.co
m/news/2013/05/method-
improves-carbon-fiber-
composites-airplanes)
(image taken from
http://newatlas.com/battelle-heatcoat-
aircraft-icing/36201/)

2. Long Chain Fibers: Nothing NewLong Chain Fibers: Nothing New
Historical Structural Basics of Fibers:Historical Structural Basics of Fibers:
Woven Fabrics (polyethylene, polyester, nylon, most commercialWoven Fabrics (polyethylene, polyester, nylon, most commercial
textiles)textiles)

Some unrefined crystalline regions, broken up by amorphous regionsSome unrefined crystalline regions, broken up by amorphous regions
Extended Chain Fibers (refined polyethylene, Kevlar, Spectra,Extended Chain Fibers (refined polyethylene, Kevlar, Spectra,
Xylon)Xylon)

Introduced a new level of straight, long-chain crystalline regions, but stillIntroduced a new level of straight, long-chain crystalline regions, but still
contained impurities and air pockets, limiting strengthcontained impurities and air pockets, limiting strength
Nano-Composites (Carbon Nanofibers, Carbon Nanotubes)Nano-Composites (Carbon Nanofibers, Carbon Nanotubes)

Offer a new level of refinement (polymer-like chains wrapped into aOffer a new level of refinement (polymer-like chains wrapped into a
strong 3D tube), but also many new levels of complexity and challengestrong 3D tube), but also many new levels of complexity and challenge
(image of (a) single-walled carbon nanotubes, (b)
few-walled carbon nanotubes, and (c) multi-walled
carbon nanotubes taken from
http://www.intechopen.com/books/carbon-
nanotubes-polymer-
nanocomposites/functionalization-of-carbon-
nanotubes)
(image taken from
http://www.ccm.udel.edu/research_summari
es/structural-hierarchy-of-ultra-high-
molecular-weight-polyethylene-uhmwpe-
fibers-studied-by-atomic-force-microscopy/)
(image taken from
http://pslc.ws/macrog/kidsmac/polyeth.htm)

3. Carbon NanotubesCarbon Nanotubes
StructuralStructural SpecificsSpecifics of Carbon Nanotubesof Carbon Nanotubes
A batch of nanotubes can have the following configurations:A batch of nanotubes can have the following configurations:

Armchair (always metallic and conductive)Armchair (always metallic and conductive)

Zigzag (often semi-conductive; seldom metallic)Zigzag (often semi-conductive; seldom metallic)

Chiral (often semi-conductive; seldom metallic)Chiral (often semi-conductive; seldom metallic)

The dream was to have a full batch of Armchair buckytubes; hasn’t happenedThe dream was to have a full batch of Armchair buckytubes; hasn’t happened
yet.yet.
Nanotubes can be single-walled or multi-walledNanotubes can be single-walled or multi-walled

Single-Wall Advantages: disperse better; usually longer and provide greaterSingle-Wall Advantages: disperse better; usually longer and provide greater
strength propertiesstrength properties

Multi-Wall Advantages: More resistant to chemical damage; good potential for aMulti-Wall Advantages: More resistant to chemical damage; good potential for a
variety of properties single-walled samples don’t providevariety of properties single-walled samples don’t provide
(image taken from http://physicsworld.com/cws/article/news/2013/feb/19/scientists-
delve-deeper-into-carbon-nanotubes)
(image taken from
http://nanophys.seas.upenn.edu/nanotube4.html)

4. So You Want to Make a Carbon NanotubeSo You Want to Make a Carbon Nanotube
Enabled Material?Enabled Material?
SynthesisSynthesis

Most common method: Chemical Vapor DepositionMost common method: Chemical Vapor Deposition
Involves passing heated hydrocarbon gas over metal catalyst nanoparticlesInvolves passing heated hydrocarbon gas over metal catalyst nanoparticles

Can also be made from Laser Ablation and Arc Discharge (similar to above, but the heatingCan also be made from Laser Ablation and Arc Discharge (similar to above, but the heating
process is different)process is different)

Plasma Enhanced CVD can producePlasma Enhanced CVD can produce alignedaligned nanotubesnanotubes

Mysteries and “Magic!”Mysteries and “Magic!”
Purification (need to remove leftover catalyst, amorphous “junk” carbon, etc., usuallyPurification (need to remove leftover catalyst, amorphous “junk” carbon, etc., usually
by oxidizing the catalyst w/ strong acids and heating; can lead to defects, but couldby oxidizing the catalyst w/ strong acids and heating; can lead to defects, but could
this be athis be a goodgood thing?)thing?)
Functionalization (need buffer chemicals to separate tubes from each other)Functionalization (need buffer chemicals to separate tubes from each other)

Covalent functionalization (hydrocarbons bond at tube ends and defect sites)Covalent functionalization (hydrocarbons bond at tube ends and defect sites)

Noncovalent functionalization (hydrocarbon surfactants or polymers that are 1 partNoncovalent functionalization (hydrocarbon surfactants or polymers that are 1 part
hydrophobic; 1 part hydrophilic, like soap!)hydrophobic; 1 part hydrophilic, like soap!)
Function
alization
Synthesis
(image taken from
http://www.intechopen.com/books/carbo
n-nanotubes-from-research-to-
applications/syntheses-of-carbon-
nanotube-metal-oxides-composites-
adsorption-and-photo-degradation)
(image taken
from
http://what-is-
nanotechnolo
gy.com/5CNT
s-dispersions-
carbon-
nanotubes-
CNTs.htm)
Purification
(image taken from
http://sti.srs.gov/fulltext/ms2001443/ms2001443.html)
(image taken from
http://www.goalfinder.com/product.asp?
productid=113)

5. Carbon Nanotube Enabled MaterialsCarbon Nanotube Enabled Materials
Potential UsesPotential Uses

Energy Conduction (best thermally conductive material known already;Energy Conduction (best thermally conductive material known already;
electrical conductivity 60 times WORSE than copper, but can be madeelectrical conductivity 60 times WORSE than copper, but can be made
into conductive polymers)into conductive polymers)

Energy Storage (batteries, capacitors, hydrogen fuel cell containment allEnergy Storage (batteries, capacitors, hydrogen fuel cell containment all
in the works)in the works)

Further possibilities in new Composites, Fibers, and FabricsFurther possibilities in new Composites, Fibers, and Fabrics
Current Real-Life UsesCurrent Real-Life Uses

High-Strength Composites being tested now (NanotubesHigh-Strength Composites being tested now (Nanotubes alonealone havehave
demonstrated an Fdemonstrated an Ftutu of 5366 ksi, though currently in composites theyof 5366 ksi, though currently in composites they
offer only some improvements over carbon fiber)offer only some improvements over carbon fiber)

James Kunda: Flight deck protection for terrorist threatsJames Kunda: Flight deck protection for terrorist threats

Greg Waugh: isolation and electrical spark protection for fuel transferGreg Waugh: isolation and electrical spark protection for fuel transfer
systems on the 787 Dreamlinersystems on the 787 Dreamliner
(image taken from
http://news.softpedia.com/news/Carbon-Nanotube-
Wires-Are-Now-Capable-of-Electrical-Conductivity-
220674.shtml)
(images taken from
http://puccini.che.pitt.edu/index2.html)
(images taken from
http://mechanosynthesis.mit.edu/2008/04/joini
ng-prepreg-composite-interfaces-with-
aligned-carbon-nanotubes/)

6. Carbon Nanotube Enabled MaterialsCarbon Nanotube Enabled Materials
Potential UsesPotential Uses

Energy Conduction (best thermally conductive material known already;Energy Conduction (best thermally conductive material known already;
electrical conductivity 60 times WORSE than copper, but can be madeelectrical conductivity 60 times WORSE than copper, but can be made
into conductive polymers)into conductive polymers)

Energy Storage (batteries, capacitors, hydrogen fuel cell containment allEnergy Storage (batteries, capacitors, hydrogen fuel cell containment all
in the works)in the works)

Further possibilities in new Composites, Fibers, and FabricsFurther possibilities in new Composites, Fibers, and Fabrics
Current Real-Life UsesCurrent Real-Life Uses

High-Strength Composites being tested now (NanotubesHigh-Strength Composites being tested now (Nanotubes alonealone havehave
demonstrated an Fdemonstrated an Ftutu of 5366 ksi, though currently in composites theyof 5366 ksi, though currently in composites they
offer only some improvements over carbon fiber)offer only some improvements over carbon fiber)

James Kunda: Flight deck protection for terrorist threatsJames Kunda: Flight deck protection for terrorist threats

Greg Waugh: isolation and electrical spark protection for fuel transferGreg Waugh: isolation and electrical spark protection for fuel transfer
systems on the 787 Dreamlinersystems on the 787 Dreamliner
(image taken from
http://news.softpedia.com/news/Carbon-Nanotube-
Wires-Are-Now-Capable-of-Electrical-Conductivity-
220674.shtml)
(images taken from
http://puccini.che.pitt.edu/index2.html)
(images taken from
http://mechanosynthesis.mit.edu/2008/04/joini
ng-prepreg-composite-interfaces-with-
aligned-carbon-nanotubes/)