Nanotube Applications and Uses
The properties of carbon nanotubes have caused researchers and companies to
consider using them in several fields. The following survey of
carbon nanotube applications introduces many of these uses.
Carbon Nanotubes and Energy
Researchers at Rice University are using carbon nanotube films to stop the growth of dendrites on lithium metal anodes. This step may help develop
lithium metal batteries, which could have much higher capacity and faster charging than lithium ion batteries.
Researchers at the University of Delaware have demonstarted
increased energy density for capacitors with the use of
carbon nanotubes in 3-D structured electrodes.
Researchers at North Carolina State University have demonstrated the
use of silicon coated carbon
nanotubes in anodes for Li-ion batteries. They are predicting
that the use of silicon can increase the capacity of Li-ion batteries by
up to 10 times. However silicon expands during a batteries discharge
cycle, which can damage silicon based anodes. By depositing silicon on
nanotubes aligned parallel to each other the researchers hope to prevent
damage to the anode when the silicon expands.
Researchers at Los Alamos National
Laboratory have demonstrated a
made from nitrogen-doped carbon-nanotubes, instead
of platinum. The researchers believe this type of
catalyst could be used in Lithium-air batteries, which
can store up to 10 times as much energy as lithium-ion
Researchers at Rice University have developed electrodes made from
carbon nanotubes grown on
graphene with very high surface area and very low electrical
resistance. The researchers first grow graphene on a metal substrate
then grow carbon nanotubes on the graphene sheet. Because the base of
each nanotube is bonded, atom to atom, to the graphene sheet the
nanotube-graphene structure is essentially one molecule with a
huge surface area.
Using carbon nanotubes in the
cathode layer of a battery that can be produced on almost any surface. The battery can be
formed by simply spraying layers of paint containing the components needed for
each part of the battery.
Carbon nanotubes can perform as a catalyst in a fuel cell, avoiding the use of expensive
platinum on which most catalysts are based. Researchers have found
that incorporating nitrogen and iron atoms into the carbon lattice of nanotubes results in nanotubes with
Read more about Carbon
Nanotubes in Energy Applications
Nanotubes In Healthcare
Researchers are improving dental implants by
nanotubes to the surface of the implant material. They have
shown that bone adheres better to titanium dioxide nanotubes than to
the surface of standard titanium implants. As well they have
demonstrated to the ability to load the nanotubes with
anti-inflammatory drugs that can be applied directly to the area
around the implant.
Reseachers at MIT have developed a sensor using carbon nanotubes
embedded in a gel; that can be injected under the skin to
monitor the level of
nitric oxide in the bloodstream. The level of nitric oxide is
important because it indicates inflamation, allowing easy monitoring of
imflammatory diseases. In tests with laboratory mice the sensor remained
functional for over a year.
Researchers have demonstrated
artificial muscles composed of yarn woven with carbon nanotubes and filled
with wax. Tests have shown that the artificial muscles can lift weights that are
200 times heavier than natural muscles of the same size.
Nanotubes bound to an antibody that is produced by chickens have been shown
to be useful in lab tests to destroy breast cancer tumors. The antibody-carrying nanotubes are attracted to proteins produced by
one type of breast cancer cell. Once attached to these cells, the nanotubes absorb light from an infrared
the nanotubes and the attached tumor.
Researchers at the University of Connecticut have developed a
sensor that uses nanotubes and gold nanoparticles to
proteins that indicate the presence of oral cancer. Tests have shown this sensor to
be accurate and it provides results in less than
Read more about
Carbon Nanotubes in Medical
Carbon Nanotubes and the Environment
Carbon nanotubes are being developed to clean up oil spills. Researchers have found that adding boron atoms during the growth of carbon nanotubes causes the
nanotubes to grow into a sponge like material
that can absorb many times it's weight in oil. These nanotube sponges
are made to be magnetic, which should make
retrieval of them easier once they are filled with oil.
Carbon nanotubes can be used as the pores in membranes to run reverse osmosis desalination plants.
Water molecules pass through the
smoother walls of carbon nanotubes more easily than through other types of nanopores,
which requires less power. Other researchers are using carbon nanotubes to
develope small, inexpensive
water purification devices needed in developing countries.
carbon nanotube detection elements are capable of detecting a range of
chemical vapors. These sensors work by reacting to the changes in the resistance
of a carbon nanotube in the presence of a chemical vapor.
Researchers at the Technische Universität München have demonstrated a
method of spraying carbon
nanotubes onto flexible plastic surfaces to produce sensors. The
researchers believe that this method could produce low cost sensors on
surfaces such as the plastic film wrapping food, so that the sensor
could detect spoiled food.
An inexpensive nanotube-based sensor can detect bacteria in drinking water.
Antibodies sensitive to a
particular bacteria are bound to the nanotubes, which are then deposited onto a paper strip. When the bacteria is present it attaches to the antibodies, changing the spacing between the nanotubes and the resistance of the
paper strip containing the nanotubes.
Carbon nanotubes tipped with gold nanoparticles can be used to trap oil drops polluting water.
Since the gold end is attracted to water while the carbon end is attracted to
oil. Therefore the nanotubes form spheres surrounding oil droplets with the
carbon end pointed in, toward the oil, and the gold end pointing out, toward the
Carbon Nanotubes Effecting Materials
Researchers at Rice University have developed a
method of depositing a film containing carbon nanotubes
that can measure the strain in a structure. The
frequency of the carbon nanotubes fluorescence changes
with the level of strain, allowing the
strain level in a structure to be measured.
Researchers are developing materials, such as a
carbon nanotube-based composite developed by NASA that bends when a
voltage is applied. Applications include the application of an
electrical voltage to change the shape (morph) of aircraft wings and other
video from NASA
gives you an idea of what a futuristic morphing aircraft might look like.
Researchers at Rice University have
demonstrated a method to reduce the
coaxial cable for aerospace applications by using a
coating of carbon nanotubes, in place of the
conventional wire braid surrounding the core of the
Researchers have found that carbon nanotubes can fill the
voids that occur in conventional concrete. These voids allow
water to penetrate concrete causing cracks, but including
nanotubes in the mix stops the cracks from forming.
Researchers at MIT have developed a method
to add carbon nanotubes aligned perpendicular to the carbon fibers,
nanostiching. They believe that having the nanotubes perpendicular
to the carbon fibers help hold the fibers together, rather than
depending upon epoxy, and significanly improve the properties of the
Avalon Aviation incorporated
nanotubes in a carbon fiber composite engine cowling
on an aerobatic aircraft to increase the strength to weight ratio. The
engine cowling is
stressed components in this aircraft, adding carbon nanotubes to the
composite allowed them to reduce the weight without weakening the
Carbon Nanotubes in Materials
Carbon Nanotubes and Electronics
transistors from carbon nanotubes enables minimum
transistor dimensions of a few nanometers and the development of techniques
circuits built with nanotube transistors.
Researchers at Stanford University have
demonstrated a method to make functioning
integrated circuits using
carbon nanotubes. In order to make the circuit work they developed
methods to remove metallic nanotubes, leaving only semiconducting
nanotubes, as well as an algorithm to deal with misaligned nanotubes.
The demonstration circuit they fabricated in the university labs
contains 178 functioning transistors.
Other applications in this area include: