Source : https://www.nano.gov/you/nanotechnology-benefits

Nanotechnology is helping to considerably improve, even revolutionize, many technology and industry sectors: information technology, homeland security, medicine, transportation, energy, food safety, and environmental science, and among many others. Described below is a sampling of the rapidly growing list of benefits and applications of nanotechnology.

Many benefits of nanotechnology depend on the fact that it is possible to tailor the structures of materials at extremely small scales to achieve specific properties, thus greatly extending the materials science toolkit. Using nanotechnology, materials can effectively be made stronger, lighter, more durable, more reactive, more sieve-like, or better electrical conductors, among many other traits. Many everyday commercial products are currently on the market and in daily use that rely on nanoscale materials and processes: Nanoscale additives to or surface treatments of fabrics can provide lightweight ballistic

energy deflection in personal body armor, or can help them resist wrinkling, staining, and bacterial growth.

Clear nanoscale films on eyeglasses, computer and camera displays, windows, and other surfaces can make them water- and residue-repellent, antireflective, self-cleaning, resistant to ultraviolet or infrared light, antifog, antimicrobial, scratch-resistant, or electrically conductive.

Nanoscale materials are beginning to enable washable, durable “smart fabrics” equipped with flexible nanoscale sensors and electronics with capabilities for health monitoring, solar energy capture, and energy harvesting through movement.

Lightweighting of cars, trucks, airplanes, boats, and space craft could lead to significant fuel savings. Nanoscale additives in polymer composite materials are being used in baseball bats, tennis rackets, bicycles, motorcycle helmets, automobile parts, luggage, and power tool housings, making them lightweight, stiff, durable, and resilient. Carbon nanotube sheets are now being produced for use in next-generation air vehicles. For example, the combination of light weight and conductivity makes them ideal for applications such as electromagnetic shielding and thermal management.  Nano-bioengineering of enzymes is aiming to enable conversion of cellulose from

wood chips, corn stalks, unfertilized perennial grasses, etc., into ethanol for fuel. Cellulosic nanomaterials have demonstrated potential applications in a wide array of industrial sectors, including electronics, construction, packaging, food, energy, health care, automotive, and defense. Cellulosic nanomaterials are projected to be less expensive than many other nanomaterials and, among other characteristics, tout an impressive strength-to-weight ratio.

Nano-engineered materials in automotive products include high-power rechargeable battery systems; thermoelectric materials for temperature control; tires with lower rolling resistance; high-efficiency/low-cost sensors and electronics; thin-film smart solar panels; and fuel additives for cleaner exhaust and extended range.

Nanostructured ceramic coatings exhibit much greater toughness than conventional wear-resistant coatings for machine parts. Nanotechnology-enabled lubricants and engine oils also significantly reduce wear and tear, which can significantly extend the lifetimes of moving parts in everything from power tools to industrial machinery.

Nanoparticles are used increasingly in catalysis to boost chemical reactions. This reduces the quantity of catalytic materials necessary to produce desired results, saving money and reducing pollutants. Two big applications are in petroleum refining and in automotive catalytic converters.

Nano-engineered materials make superior household products such as degreasers and stain removers; environmental sensors, air purifiers, and filters; antibacterial cleansers; and specialized paints and sealing products, such a self-cleaning house paints that resist dirt and marks.

Nanoscale materials are also being incorporated into a variety of personal care products to improve performance. Nanoscale titanium dioxide and zinc oxide have been used for years in sunscreen to provide protection from the sun while appearing invisible on the skin. 

Electronics and IT applications-Nanotechnology has greatly contributed to major advances in computing and electronics, leading to faster, smaller, and more portable systems that can manage and store larger and larger amounts of information. These continuously evolving applications include: Transistors, the basic switches that enable all modern computing, have gotten smaller and

smaller through nanotechnology. At the turn of the century, a typical transistor was 130 to 250 nanometers in size. In 2014, Intel created a 14 nanometer transistor, then IBM created the first seven nanometer transistor in 2015, and then Lawrence Berkeley National Lab demonstrated a one nanometer transistor in 2016!  Smaller, faster, and better transistors may mean that soon your computer’s entire memory may be stored on a single tiny chip.

Using magnetic random access memory (MRAM), computers will be able to “boot” almost instantly. MRAM is enabled by nanometer‐scale magnetic tunnel junctions and can quickly and effectively save data during a system shutdown or enable resume‐play features.

Ultra-high definition displays and televisions are now being sold that use quantum dots to produce more vibrant colors while being more energy efficient.

Flexible, bendable, foldable, rollable, and stretchable electronics are reaching into various sectors and are being integrated into a variety of products, including  wearables, medical applications, aerospace applications, and the Internet of Things. Flexible electronics have been developed using, for example, semiconductor nanomembranes for applications in smartphone and e-reader displays. Other nanomaterials like graphene and cellulosic nanomaterials are being used for various types of flexible electronics to enable wearable and “tattoo” sensors, photovoltaics that can be sewn onto clothing, and electronic paper that can be rolled up. Making flat, flexible, lightweight, non-brittle, highly efficient electronics opens the door to countless smart products.   

Other computing and electronic products include Flash memory chips for smart phones and thumb drives; ultra-responsive hearing aids; antimicrobial/antibacterial coatings on keyboards and cell phone casings; conductive inks for printed electronics for RFID/smart cards/smart packaging; and flexible displays for e-book readers.

Nanoparticle copper suspensions have been developed as a safer, cheaper, and more reliable alternative to lead-based solder and other hazardous materials commonly used to fuse electronics in the assembly process.

Medical and Health Care applications :

Nanotechnology is already broadening the medical tools, knowledge, and therapies currently available to clinicians. Nanomedicine, the application of nanotechnology in medicine, draws on the natural scale of biological phenomena to produce precise solutions for disease prevention, diagnosis, and treatment. Below are some examples of recent advances in this area:  Commercial applications have adapted gold nanoparticles as probes for the detection of

targeted sequences of nucleic acids, and gold nanoparticles are also being clinically investigated as potential treatments for cancer and other diseases.

Better imaging and diagnostic tools enabled by nanotechnology are paving the way for earlier diagnosis, more individualized treatment options, and better therapeutic success rates.

Nanotechnology is being studied for both the diagnosis and treatment of atherosclerosis, or the buildup of plaque in arteries. In one technique, researchers created a nanoparticle that mimics the body’s “good” cholesterol, known as HDL (high-density lipoprotein), which helps to shrink plaque. 

The design and engineering of advanced solid-state nanopore materials could allow for the development of novel gene sequencing technologies that enable single-molecule detection at low cost and high speed with minimal sample preparation and instrumentation.

Nanotechnology researchers are working on a number of different therapeutics where a nanoparticle can encapsulate or otherwise help to deliver medication directly to cancer cells and minimize the risk of damage to healthy tissue. This has the potential to change the way doctors treat cancer and dramatically reduce the toxic effects of chemotherapy.

Research in the use of nanotechnology for regenerative medicine spans several application areas, including bone and neural tissue engineering. For instance, novel materials can be engineered to mimic the crystal mineral structure of human bone or used as a restorative resin for dental applications. Researchers are looking for ways to grow complex tissues with the goal of one day growing human organs for transplant. Researchers are also studying ways to use graphene nanoribbons to help repair spinal cord injuries; preliminary research shows that neurons grow well on the conductive graphene surface.  

Nanomedicine researchers are looking at ways that nanotechnology can improve vaccines, including vaccine delivery without the use of needles. Researchers also are working to create a universal vaccine scaffold for the annual flu vaccine that would cover more strains and require fewer resources to develop each year.

Energy Applications:Nanotechnology is finding application in traditional energy sources and is greatly enhancing alternative energy approaches to help meet the world’s increasing energy demands. Many scientists are looking into ways to develop clean, affordable, and renewable energy sources, along with means to reduce energy consumption and lessen toxicity burdens on the environment: Nanotechnology is improving the efficiency of fuel production from raw petroleum

materials through better catalysis. It is also enabling reduced fuel consumption in vehicles and power plants through higher-efficiency combustion and decreased friction.

Nanotechnology is also being applied to oil and gas extraction through, for example, the use of nanotechnology-enabled gas lift valves in offshore operations or the use of nanoparticles to detect microscopic down-well oil pipeline fractures. 

Researchers are investigating carbon nanotube “scrubbers” and membranes tosearate carbon dioxide from power plant exhaust.

Researchers are developing wires containing carbon nanotubes that will have much lower resistance than the high-tension wires currently used in the electric grid, thus reducing transmission power loss.

Nanotechnology can be incorporated into solar panels to convert sunlight to electricity more efficiently, promising inexpensive solar power in the future. Nanostructured solar cells could be cheaper to manufacture and easier to install, since they can use print-like manufacturing processes and can be made in flexible rolls rather than discrete panels. Newer research suggests that future solar converters might even be “paintable.”

Nanotechnology is already being used to develop many new kinds of batteries that are quicker-charging, more efficient, lighter weight, have a higher power density, and hold electrical charge longer. 

An epoxy containing carbon nanotubes is being used to make windmill blades that are longer, stronger, and lighter-weight than other blades to increase the amount of electricity that windmills can generate.

In the area of energy harvesting, researchers are developing thin-film solar electric panels that can be fitted onto computer cases and flexible piezoelectric nanowires woven into clothing to generate usable energy on the go from light, friction, and/or body heat to power mobile electronic devices. Similarly, various nanoscience-based options are being pursued to convert waste heat in computers, automobiles, homes, power plants, etc., to usable electrical power. 

Energy efficiency and energy saving products are increasing in number and types of application. In addition to those noted above, nanotechnology is enabling more efficient lighting systems; lighter and stronger vehicle chassis materials for the transportation sector; lower energy consumption in advanced electronics; and light-responsive smart coatings for glas

Environmental Applications

In addition to the ways that nanotechnology can help improve energy efficiency (see the section above), there are also many ways that it can help detect and clean up environmental contaminants: Nanotechnology could help meet the need for affordable, clean drinking water through

rapid, low-cost detection and treatment of impurities in water.  Engineers have developed a thin film membrane with nanopores for energy-efficient

desalination. This molybdenum disulphide (MoS2) membrane filtered two to five times more water than current conventional filters.

Nanoparticles are being developed to clean industrial water pollutants in ground water through chemical reactions that render the pollutants harmless. This process would cost less than methods that require pumping the water out of the ground for treatment.

Researchers have developed a nanofabric "paper towel" woven from tiny wires of potassium manganese oxide that can absorb 20 times its weight in oil for cleanup applications. Researchers have also placed magnetic water-repellent nanoparticles in oil spills and used magnets to mechanically remove the oil from the water.

Many airplane cabin and other types of air filters are nanotechnology-based filters that allow “mechanical filtration,” in which the fiber material creates nanoscale pores that trap particles larger than the size of the pores. The filters also may contain charcoal layers that remove odors. 

Nanotechnology-enabled sensors and solutions are now able to detect and identify chemical or biological agents in the air and soil with much higher sensitivity than ever before. Researchers are investigating particles such as self-assembled monolayers on mesoporous supports (SAMMS™), dendrimers, and carbon nanotubes to determine how to apply their unique chemical and physical properties for various kinds of toxic site remediation. Another sensor has been developed by NASA as a smartphone extension that firefighters can use to monitor air quality around fires.

Future Transportation applicationsNanotechnology offers the promise of developing multifunctional materials that will contribute to building and maintaining lighter, safer, smarter, and more efficient vehicles, aircraft, spacecraft, and ships. In addition, nanotechnology offers various means to improve the transportation infrastructure: As discussed above, nano-engineered materials in automotive products include polymer

nanocomposites structural parts; high-power rechargeable battery systems; thermoelectric materials for temperature control; lower rolling-resistance tires; high-efficiency/low-cost sensors and electronics; thin-film smart solar panels; and fuel additives and improved catalytic converters for cleaner exhaust and extended range. Nano-engineering of aluminum, steel, asphalt, concrete and other cementitious materials, and their recycled forms offers great promise in terms of improving the performance, resiliency, and longevity of highway and transportation infrastructure components while reducing their life cycle cost. New systems may incorporate innovative capabilities into traditional infrastructure materials, such as self-repairing structures or the ability to generate or transmit energy.

Nanoscale sensors and devices may provide cost-effective continuous monitoring of the structural integrity and performance of bridges, tunnels, rails, parking structures, and pavements over time. Nanoscale sensors, communications devices, and other innovations enabled by nanoelectronics can also support an enhanced transportation infrastructure that

can communicate with vehicle-based systems to help drivers maintain lane position, avoid collisions, adjust travel routes to avoid congestion, and improve drivers’ interfaces to onboard electronics. 

“Game changing” benefits from the use of nanotechnology-enabled lightweight, high-strength materials would apply to almost any transportation vehicle. For example, it has been estimated that reducing the weight of a commercial jet aircraft by 20 percent could reduce its fuel consumption by as much as 15 percent. A preliminary analysis performed for NASA has indicated that the development and use of advanced nanomaterials with twice the strength of conventional composites would reduce the gross weight of a launch vehicle by as much as 63 percent. Not only could this save a significant amount of energy needed to launch spacecraft into orbit, but it would also enable the development of single stage to orbit launch vehicles, further reducing launch costs, increasing mission reliability, and opening the door to alternative propulsion concepts.

AerogelAerogel’ is a highly porous, solid foam, with well connected nanostructures. It is

generally made of silica and can have several shapes and forms. However, organic polymers, carbon, copper, gold and semiconductor nanostructures are also capable of forming aerogels. About 99.8% of the aerogel structure is nothing but thin air, giving it a ghostly appearance and earning it the name of ‘solid smoke’. Aerogels are produced by extracting the liquid component of a gel through supercritical drying. This allows the liquid to be slowly dried off without causing the solid matrix in the gel to collapse from capillary action, as would happen with conventional evaporation. The first aerogels were produced from silica gels. 

The key properties of aerogels are listed below:

Extreme lightness - density range - 0.0011 to 0.5 g cm-3

Low thermal conductivity Low mean free path of diffusion High specific surface area for non-powder materials High strength Low refractive index Low sound speed Low dielectric constant

The major applications of aerogels are the following:

As insulating material in spacesuits To capture comet dust In insulating boards and wall insulation

Dimensions of nanomaterialsThe main types of nanostructured materials based on the dimensions of their structural

elements are: zero-dimensional (0D), one-dimensional (1D), two-dimensional (2D) and three-dimensional (3D) nanomaterials.This classification is based on the number of dimensions of a material, which are outside the nanoscale (<100 nm) range

Zero dimensional(0-D):These nanomaterials have Nano-dimensions in all the three directions. Metallic nanoparticles including gold and silver nanoparticles and semiconductor such as quantam dots are the perfect example of this kind of nanoparticles. Most of these nanoparticles are spherical in size and the diameter of these particles will be in the1-50 nm range. Cubes and polygons shapes are also found for this kind of nanomaterials.

2. One dimensional(1-D):In these nanostructures, one dimension of the nanostructure will be outside the nanometer range. These include nanowires, nanorods, and nanotubes. These materials are long (several micrometer in length), but with diameter of only a few nanometer. Nanowire and nanotubes of metals, oxides and other materials are few examples of this kind of materials

3. Two dimensional(2-D):In this type of nanomaterials, two dimensions are outside the nanometer range. These include different kind of Nano films such as coatings and thin-film-multilayers, nano sheets or nano-walls. The area of the nano films can be large (several square micrometer),but the thickness is always in nano scale range

4. Three Dimensional(3-D):All dimensions of these are outside the nano meter range. These include bulk materials composed of the individual blocks which are in the nanometer scale (1-100 nm) This class can contain bulk powders, dispersions of nanoparticles, bundles of nanowires, and nanotubes as well as multi-nanolayers.

Classification of nanoscale dimensions. (Source: Tallinn University of Technology)

The key differences between nanomaterials and bulk materials

Two principal factors cause the properties of nanomaterials to differ significantly from other materials: increased relative surface area, and quantum effects. These factors can change or enhance properties such as reactivity, strength and electrical characteristics.As a particle decreases in size, a greater proportion of atoms are found at the surface compared to those inside. For example, a particle of size 30 nm has 5% of its atoms on its surface, at 10 nm 20% of its atoms, and at 3 nm 50% of its atoms.Thus nanoparticles have a much greater surface area per unit mass compared with larger particles. As growth and catalytic chemical reactions occur at surfaces, this means that a given mass of material in nanoparticulate form will be much more reactive than the same mass of material made up of larger particles.

Properties of nanomaterials

In tandem with surface-area effects, quantum effects can begin to dominate the properties of matter as size is reduced to the nanoscale. These can affect the optical, electrical and magnetic behaviour of materials, particularly as the structure or particle size approaches the smaller end of the nanoscale. Materials that exploit these effects include quantum dots, and quantum well lasers for optoelectronics.For other materials such as crystalline solids, as the size of their structural components decreases, there is much greater interface area within the material; this can greatly affect both mechanical and electrical properties.For example, most metals are made up of small crystalline grains; the boundaries between the grain slow down or arrest the propagation of defects when the material is stressed, thus giving it strength. If these grains can be made very small, or even nanoscale in size, the interface area within the material greatly increases, which enhances its strength. For example, nanocrystalline nickel is as strong as hardened steel.

Excerpted from Nanotechnology For Dummies (2nd edition), from Wiley Publishing

What are the potential health effects of nanomaterials?There is experimental evidence of a range of possible interactions with biological

systems and health effects of manufactured nanoparticles. In experimental systems in the laboratory they can affect the formation of the fibrous protein tangles which are similar to those seen in some diseases, including brain diseases. Airborne particles might cause effects in the lungs but also on the heart and blood circulation similar to those already known for particulate air pollution. There is some evidence that nanoparticles might lead to genetic damage, either directly or by causing inflammation.

All these effects would depend on nanoparticles’ fate in the body. Only a minimal amount of nanoparticle doses escape the lungs or intestine, but long-term exposure could still mean a large number are distributed round the body. Most are held in the liver or the spleen, but some appear to reach all tissues and organs. There may also be entry into the brain via the membranes inside the nose.Nanotubes or rods with similar characteristics to asbestos fibres pose a risk of the mesothelioma (a form of cancer of the pleura).

What are the potential environmental effects of nanomaterials?Increased production and use of nanomaterials will lead to an increase in

environmental exposure. Estimation of relevant exposures is hampered by lack of knowledge about rates of release or concentrations of nanomaterials in the environment. Existing theory on behaviour of chemicals and particulates in the environment is not necessarily applicable to nanomaterials. Current thinking on what happens to nanomaterials in the environment is based on general considerations rather than much in the way of direct measurement and assessment.

The behaviour of nanomaterials in the environment depends as much on where they are released as on the materials themselves. Important conditions include acidity (pH), presence or absence of charged ions, and levels of organic matter in the environment (water). As with other small particles, nanomaterials might:

Dissolve Latch on to other chemical molecules or ions Be transformed into other chemicals by action of organisms, or undergo

mineralization or partial or complete degradation. Clump together, and unclump, depending on conditions Settle out into sediment

Estimates of quantities of nanomaterials in surface waters, for instance, are based on predicted nanomaterial use rather than actual measurements.

Future measurements will need to take account of the possibility of “hot spots”. These are places where particles are concentrated, perhaps by agglomeration, or interaction with organic matter. Wastewater treatment plants will be likely sites for accumulation of some nanomaterials in sewage.

There is also the possibility of bioaccumulation, in which nanomaterials are concentrated in particular organs of a species which is exposed. As aggregated nanomaterials are likely to end up in sediments, bioaccumulation studies on organisms which dwell in sediments are especially important.

What is a buckyball or fullereneBuckyballs, also called fullerenes, were one of the first nanoparticles discovered. This

discovery happened in 1985 by a trio of researchers working out of Rice University named Richard Smalley, Harry Kroto, and Robert Curl.

Buckyballs are composed of carbon atoms linked to three other carbon atoms by covalent bonds. However, the carbon atoms are connected in the same pattern of hexagons and pentagons you find on a soccer ball, giving a buckyball the spherical structure as shown in the following figure.

   

A buckyball.

The most common buckyball contains 60 carbon atoms and is sometimes called C60.Other sizes of buckyballs range from those containing 20 carbon atoms to those containing more than 100 carbon atoms.

The covalent bonds between carbon atoms make buckyballs very strong, and the carbon atoms readily form covalent bonds with a variety of other atoms. Buckyballs are used in composites to strengthen material. Buckyballs have the interesting electrical property of being very good electron acceptors, which means they accept loose electrons from other materials. This feature is useful, for example, in increasing the efficiency of solar cells in transforming sunlight into electricity.

The properties of buckyballs (also known as fullerenes) have caused researchers and companies to consider using them in several fields.

Buckyballs may be used to trap free radicals generated during an allergic reaction and block the inflammation that results from an allergic reaction.

The antioxidant properties of buckyballs may be able to fight the deterioration of motor function due to multiple sclerosis.

Combining buckyballs, nanotubes, and polymers to produce inexpensive solar cells that can be formed by simply painting a surface.

Buckyballs may be used to store hydrogen, possibly as a fuel tank for fuel cell powered cars.

Buckyballs may be able to reduce the growth of bacteria in pipes and membranes in water systems.

Researchers are attempting to modify buckyballs to fit the section of the HIV molecule that binds to proteins, possibly inhibiting the spread of the virus.

Making bullet proof vests with inorganic (tungsten disulfide) buckyballs.

What are Carbon Nanotubes?

A significant nanoparticle discovery that came to light in 1991 was carbon nanotubes. Where buckyballs are round, nanotubes are cylinders that haven’t folded around to create a sphere. Carbon nanotubes are composed of carbon atoms linked in hexagonal shapes, with each carbon atom covalently bonded to three other carbon atoms. Carbon nanotubes have diameters as small as 1 nm and lengths up to several centimeters. Although, like buckyballs, carbon nanotubes are strong, they are not brittle. They can be bent, and when released, they will spring back to their original shape.

One type of carbon nanotube has a cylindrical shape with open ends, as shown in the following figure.

A carbon nanotube.

Another type of nanotube has closed ends, formed by some of the carbon atoms combining into pentagons on the end of the nanotube, as shown in the following figure.

A carbon nanotube with closed ends.

The properties of nanotubes have caused researchers and companies to consider using them in several fields. For example, because carbon nanotubes have the highest strength-to-weight ratio of any known material, researchers at NASA are combining carbon nanotubes with other materials into composites that can be used to build lightweight spacecraft.

Carbon nanotubes can occur as multiple concentric cylinders of carbon atoms, called multi-walled carbon nanotubes (MWCTs) and shown in the following figure. Logically enough, carbon nanotubes that have only one cylinder are called single-walled carbon nanotubes (SWCTs). Both MWCT and SWCT are used to strengthen composite materials.

A multi-walled carbon nanotube.

 Carbon Nanotubes and EnergyResearchers at the University of Delaware have demonstarted increased energy

density for capacitors whit 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 catalyst 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 batteries.

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 catalytic properties.

Carbon Nanotubes In HealthcareResearchers are improving dental implants by adding 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 laser, incinerating the nanotubes and the attached tumor.

Researchers at the University of Connecticut have developed a sensor that uses nanotubes and gold nanoparticles to detect proteins that indicate the presence of oral cancer. Tests have shown this sensor to be accurate and it provides results in less than an hour.

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.

Sensors using 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 water.

Carbon Nanotubes Effecting Materials

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 structures.

Researchers at Rice University have demonstrated a method to reduce the weight of coaxial cable for aerospace applications by using a coating of carbon nanotubes, in place of the conventional wire braid surrounding the core of the cable.

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 mixstops the cracks from forming.

Researchers at MIT have developed a method  to add carbon nanotubes aligned perpendicular to the carbon fibers, called 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 composite.

Avalon Aviation incorporated carbon  nanotubes in a carbon fiber composite engine cowling on an aerobatic aircraft to increase the strength to weight ratio. The engine cowling is highly stressed components in this aircraft, adding carbon nanotubes to the composite allowed them to reduce the weight without weakening the component.

Carbon Nanotubes and ElectronicsBuilding transistors from carbon nanotubes enables minimum transistor

dimensions of a few nanometers and the development of techniques to manufacture integrated 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:

Carbon nanotubes used to direct electrons to illuminate pixels, resulting in a lightweight, millimeter thick "nanoemissive" display panel.

Printable electronic devices using nanotube "ink" in inkjet printers Transparent, flexible electronic devices using arrays of nanotubes.

What is Graphene?

Although carbon can form three-dimensional lattices by bonding with four other carbon atoms to form diamond, it can also form two-dimensional sheets (a sheet of paper has only two dimensions, for example) when it bonds to three other carbon atoms. These sheets are called graphene.

Researchers have only recently (2004) been successful in producing sheets of graphene for research purposes, though they all probably had a handy form of graphene in their pocket protectors. Common graphite is the material in pencil lead, and it’s composed of sheets of graphene stacked together. The sheets of graphene in graphite have a space between each sheet, as illustrated in the following figure, and the sheets are held together by the electrostatic force called van der Waals bonding.

Sheets of graphene held together by van der Waals bonding make graphene.

Graphene sheets are composed of carbon atoms linked in hexagonal shapes, as shown in the following figure, with each carbon atom covalently bonded to three other carbon atoms. Each sheet of graphene is only one atom thick and each graphene sheet is considered a single molecule. Graphene has the same structure of carbon atoms linked in hexagonal shapes to form carbon nanotubes, but graphene is flat rather than cylindrical.

A graphene sheet

The properties of graphene, carbon sheets that are only one atom thick, have caused researchers and companies to consider using this material in several fields. The following survey of research activity introduces you to many potential applications of graphene.

Applications:

Hydrogen production without platinum. Researchers have demonstrated a catalyst made from graphene doped with cobalt can be used to produce hydrogen from water. The researchers at looking at this method as a low cost replacement for platinum based catalysts.

Lower cost of display screens in mobile devices. Researchers have found that graphene can replace indium-based electrodes in organic light emitting diodes (OLED). These diodes are used in electronic device display screens which require low power consumption. The use of graphene instead of indium not only reduces the cost but eliminates the use of metals in the OLED, which may make devices easier to recycle.

Lithium-ion batteries that recharge faster. These batteries use graphene on the surface of the anode surface. Defects in the graphene sheet (introduced using a heat treatment) provide pathways for the lithium ions to attach to the anode substate. Studies have shown that the time needed to recharge a battery using the graphene anode is much shorter than with conventional lithium-ion batteries.

Ultracapacitors with better performance than batteries. These ultracapacitors store electrons on graphene sheets, taking advantage of the large surface of graphene to provide increase the electrical power that can be stored in the capacitor. Researchers are projecting that these ultracapacitors will have as much electrical storage capacity as lithium ion batteries but will be able to be recharged in minutes instead of hours.

Components with higher strength to weight ratios. Researchers have found that adding graphene to epoxy composites may result in stronger/stiffer components than epoxy composites using a similar weight of carbon nanotubes. Graphene appears to bond better to the polymers in the epoxy, allowing a more effective coupling of the graphene into the structure of the composite. This property could result in the manufacture of components with high strength to weight ratio for such uses as windmill blades or aircraft components.

Storing hydrogen for fuel cell powered cars. Researchers have prepared graphene layers to increase the binding energy of hydrogen to the graphene surface in a fuel tank, resulting in a higher amount of hydrogen storage and therefore a lighter weight fuel tank. This could help in the development of practical hydrogen fueled cars.

Lower cost fuel cells. Researchers at Ulsan National Institute of Science and Technology have demonstrated how to produce edge-halogenated graphene nanoplatelets that have good catalytic properties. The researchers prepared the nanoplatelets by ball-milling graphene flakes in the presence of chlorine, bromine or iodine. They believe these halogenated nanoplatelets could be used as a replacement for expensive platinum catalystic material in fuel cells.

Low cost water desalination: Researchers have determined that graphene with holes the size of a nanometer or less can be used to remove ions from water. They believe this can be used to desalinate sea water at a lower cost than the reverse osmosis techniques currently in use.

Lightweight natural gas tanks: Researchers at Rice University have developed a composite material using plastic and graphene nanoribbons that block the passage of gas molecules.

This material may be used in applications ranging from soft drink bottles to lightweight natural gas tanks.

More efficient dye sensitized solar cells. Researchers at Michigan Technological University have developed a honeycomb like structure of graphene in which the graphene sheets are held apart by lithium carbonate. They have used this "3D graphene" to replace the platinum in a dye sensitized solar cell and achieved 7.8 percent conversion of sunlight to electricity.

Electrodes with very high surface area and very low electrical resistance. Researchers at Rice University have developed electrodes made from carbon nanotubes grown on graphene. 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.

Lower cost solar cells: Researchers have built a solar cell that uses graphene as a electrode while using buckyballs and carbon nanotubes to absorb light and generate electrons; making a solar cell composed only of carbon. The intention is to eliminate the need for higher cost materials, and complicated manufacturing techniques needed for conventional solar cells.

Transistors that operate at higher frequency. The ability to build high frequency transistors with graphene is possible because of the higher speed at which electrons in graphene move compared to electrons in silicon. Researchers are also developing lithography techniques that can be used to fabricate integrated circuits based on graphene.

Sensors to diagnose diseases. These sensors are based upon graphene's large surface area and the fact that molecules that are sensitive to particular diseases can attach to the carbon atoms in graphene. For example, researchers have found that graphene, strands of DNA, and fluorescent molecules can be combined to diagnose diseases. A sensor is formed by attaching fluorescent molecules to single strand DNA and then attaching the DNA to graphene.  When an identical single strand DNA combines with the strand on the graphene a double strand DNA if formed that floats off from the graphene, increasing the fluorescence level. This method results in a sensor that can detect the same DNA for a particular disease in a sample.

Membranes for more efficient separation of gases. These membranes are made from sheets ofgraphene in which nanoscale pores have been created. Because graphene is only one atom thick researchers believe that gas separation will require less energy than thicker membranes.

Chemical sensors effective at detecting explosives. These sensors contain sheets of graphene in the form of a foam which changes resistance when low levels of vapors from chemicals, such as ammonia, is present. 

Nanocomposites, their Uses and ApplicationsComposite materials are prepared from the combination of two or more different

materials with distinct chemical or physical characteristics. The resultant composite exhibits properties which are distinct (and hopefully superior!) to its constituent materials, which remain separate and distinct within the finished structure and are not held together by formal chemical bonds. In nanocomposites, either one of the constituents has dimensions on the nanoscale (<100 nm) or instead the composite structure exhibits nanosized phase separation of the individual components.

By far the most extensive industrial usage of composite materials relates to polymeric matrices reinforced with glass or carbon fibres.  These form the mainstay of many important application areas in aerospace, land transport, marine, sports goods and a number of other industrial sectors.  In general, however, these materials are mature and highly-developed.  Work in the Department tends to focus on other types of composite, designed for more specialised applications.

Composites and nanocomposites can be prepared from a variety of different materials, depending on their intended application. The following areas are currently under exploration in the department.

Within the medical materials field, resorbable composites offer huge potential for controlled degradation and tailored temporary support to a healing site.  Particle size and composition can be used to influence the mechanics and degradation profiles and active agents may be incorporated with sustained release tied to the degradation kinetics.  Applications include resorbable cardiovascular stents and orthopaedic implants.

A nanocomposite is a matrix to which nanoparticles have been added to improve a particular property of the material. 

Applications of nanocomposites:Producing batteries with greater power output. Researchers have developed a method to make anodes for lithium ion batteries from a composite formed with silicon nanospheres and carbon nanoparticles. The anodes made of the silicon-carbon nanocomposite make closer contact with the lithium electrolyte, which allows faster charging or discharging of power.Speeding up the healing process for broken bones. Researchers have shown that growth of replacement bone is speeded up when a nanotube-polymer nanocomposite is placed as a kind of scaffold which guides growth of replacement bone. The researchers are conducting studies to better understand how this nanocomposite increases bone growth.Producing structural components with a high strength-to-weight ratio.  For example an epoxy containing carbon nanotubes can be used to produce nanotube-polymer composite windmill blades. This results in a strong but lightweight blade, which makes longer windmill blades practical. These longer blades increase the amount of electricity generated by each windmill.Using graphene to make composites with even higher strength-to-weight ratios. Researchers have found that adding graphene to epoxy composites may result in stronger/stiffer components than epoxy composites using a similar weight of carbon nanotubes. Graphene appears to bond better to the polymers in the epoxy, allowing a more effective coupling of the graphene into the structure of the composite. This property could result in the manufacture of components with higher strength-to-weight ratios for such uses as windmill blades or aircraft components.Making lightweight sensors with nanocomposites. A polymer-nanotubenanocomposite conducts electricity; how well it conducts depends upon the spacing of the nanotubes. This property allows patches of polymer-nanotube nanocomposite to act as stress sensors on

windmill blades. When strong wind gusts bend the blades the nanocomposite will also bend. Bending changes the nanocomposite sensor's electrical conductance, causing an alarm to be sounded. This alarm would allow the windmill to be shut down before excessive damage occurs.Using nanocomposites to make flexible batteries. A nanocomposite of cellulous materials and nanotubes could be used to make a conductive paper. When this conductive paper is soaked in an electrolyte, a flexible battery is formed.Making tumors easier to see and remove. Researchers are attempting to join magnetic nanoparticles and fluorescent nanoparticles in a nanocomposite particle that is both magnetic and fluorescent. The magnetic property of the nanocomposite particle makes the tumor more visible during an MRI procedure  done prior to surgery. The fluorescent property of the nanocomposite particle could help the surgeon to better see the tumor while operating.

Nanoparticles Nanoparticles have one dimension that measures 100 nanometers or less. The

properties of many conventional materials change when formed from nanoparticles. This is typically because nanoparticles have a greater surface area per weight than larger particles which causes them to be more reactive to some other molecules.

Nanoparticle Applications in Medicine

The use of polymeric micelle nanoparticles to deliver drugs to tumors.The use of polymer coated iron oxide nanoparticles to break up clusters of bacteria, possibly allowing more effective treatment of chronic bacterial infections.The surface change of protein filled nanoparticles has been shown to affect the ability of the nanoparticle to stimulate immune responses. Researchers are thinking that these nanoparticles may be used in inhalable vaccines.Researchers at Rice University have demonstrated that cerium oxide nanoparticles act as an antioxidant to remove oxygen free radicals that are present in a patient's bloodstream following a traumatic injury. The nanoparticles absorb the oxygen free radicals and then release the oxygen in a less dangerous state, freeing up the nanoparticle to absorb more free radicals.Researhers are developing ways to use carbon nanoparticles called nanodiamonds in medical applications. For example nanodiamonds with protein molecules attached can be used to increase bone growth around dental or joint implants.Researchers are testing the use of chemotherapy drugs attached to nanodiamonds to treat brain tumors. Other researchers are testing the use of chemotherapy drugs attached to nanodiamonds to treat leukemia.

Nanoparticle Applications in Manufacturing and Materials

 Ceramic silicon carbide nanoparticles dispersed in magnesium produce a strong, lightweight material.

A synthetic skin that may be used in prosthetics has been demonstrated with both self healing capability and the ability to sense pressure. The material is a composite of nickel nanoparticles and a polymer. If the material is held together after a cut it seals together in about 30 minutes giving it a self healing ability. Also the electrical resistance of the material changes with pressure, giving it a sense ability like touch.

Silicate nanoparticles can be used to provide a barrier to gasses (for example oxygen), or moisture in a plastic film used for packaging. This could slow down the process of spoiling or drying out in food.

Zinc oxide nanoparticles can be dispersed in industrial coatings to protect wood, plastic, and textiles from exposure to UV rays.

Silicon dioxide crystalline nanoparticles can be used to fill gaps between carbon fibers, thereby strengthening tennis racquets.

Silver nanoparticles in fabric are used to kill bacteria, making clothing odor-resistant.

Nanoparticle Applications and the Environment

Researchers are using photocatalytic copper tungsten oxide nanoparticles to break down oil into biodegradable compounds. The nanoparticles are in a grid that provides high surface area for the reaction, is activated by sunlight and can work in water, making them useful for cleaning up oil spills.

Researchers are using gold nanoparticles embedded in a porous manganese oxide as a room temperature catalyst to breakdown volatile organic pollutants in air.

Iron nanoparticles are being used to clean up carbon tetrachloride pollution in ground water.

Iron oxide nanoparticles are being used to clean arsenic from water wells.

Nanoparticle Applications in Energy and Electronics

Researchers have used nanoparticles called nanotetrapods studded with nanoparticles of carbon to develop low cost electrodes for fuel cells. This electrode may be able to replace the expensive platinum needed for fuel cell catalysts.

Researchers at Georgia Tech, the University of Tokyo and Microsoft Research have developed a method to print prototype circuit boards using standard inkjet printers. Silver nanoparticle ink was used to form the conductive lines needed in circuit boards.

Combining gold nanoparticles with organic molecules creates a transistor known as a NOMFET (Nanoparticle Organic Memory Field-Effect Transistor). This transistor is unusual in that it can function  in a way similar to synapses in the nervous system.

A catalyst using platinum-cobalt nanoparticles is being developed for fuel cells that produces twelve times more catalytic activity than pure platinum. In order to achieve this

performance, researchers anneal nanoparticles to form them into a crystalline lattice, reducing the spacing between platinum atoms on the surface and increasing their reactivity.

Researchers have demonstrated that sunlight, concentrated on nanoparticles, can produce steam with high energy efficiency. The "solar steam device" is intended to be used in areas of developing countries without electricity for applications such as purifying water or disinfecting dental instruments.

A lead free solder reliable enough for space missions and other high stress environments using copper nanoparticles.

Silicon nanoparticles coating anodes of lithium-ion batteries can increase battery power and reduce recharge time.

Semiconductor nanoparticles are being applied in a low temperature printing process that enables the  manufacture of low cost solar cells.

A layer of closely spaced palladium nanoparticles is being used in a hydrogen sensor. When hydrogen is absorbed, the palladium nanoparticles swell, causing shorts between nanoparticles. These shorts lower the resistance of the palladium layer.

Nanofibers: Uses and Applications of Nanofibers

A nanofiber is a fiber with a diameter of 100 nanometers or less. The properties of nanofibers have caused researchers and companies to consider using this material in several fields.

Applications of nanofibers:

Researchers are using nanofibers to capture individual cancer cells circulating in the blood stream. They use nanofibers coated with antibodies that bind to cancer cells, trapping the cancer cell for analysis.

Nanofibers can stimulate the production of cartilage in damaged joints. Three different approaches to the use of nanofibers to stimulate cartilage are being taken by researchers at John Hopkins University, at Northwestern University and at the University of Pennsylvania.

Reseachers are using nanofibers to delivery thrapeutic drugs. The have developed an elastic material that is embedded with needle like carbon nanofibers. The material is intended to be used as balloons which are inserted next diseased tissue, and then inflated. When the balloon is inflated the carbon nanofibers penetrate diseased cells and delivery therapeutic drugs.

Researchers at MIT have used carbon nanofibers to make lithium ion battery electrodes that show four times the storage capacity of current lithium ion batteries.

The next step beyond lithium-ion batteries may be lithium sulfur batteries (the cathode contains the sulfur), which have the capability of storing several times the energy of lithium-ion  batteries. Researchers at Stanford University are using cathodes made up of carbon nanofibers encapsulating the sulfur.

Researchers are using nanofibers to make sensors that change color as they absorb chemical vapors. They plan to use these sensors to show when the absorbing material in a gas mask becomes saturated.

Researchers have developed piezoelectric nanofibers that are flexible enough to be woven into clothing. The fibers can turn normal motion into electricity to power your cell phone and other mobile electronic devices.   

Flame retardant formed by coating the foam used in furniture with carbon nanofibers. 

Nanowires: Uses and Applications of Nanowires

The properties of nanowires have caused researchers and companies to consider using this material in several fields.

Nanowires Applications in Energy

Researchers at MIT have developed a solar cell using graphene coated with zinc oxide nanowires. The researchers believe that this method will allow the production of low cost flexible solar cells at high enough efficiency to be competive.

Researchers at NTU Singapore are using manganese dioxide nanowires to develop flexible capacitors. The idea is to have the capacitors in fabric to provide energy storage for wearable electronics.

Sensors powered by electricity generated by piezoelectric zinc oxide nanowires. This could allowsmall, self contained, sensors powered by mechanical energy such as tides or wind

Researchers are using a method called Aerotaxy to grow semiconducting nanowires on gold nanoparticles. They plan to use self assembly techniques to align the nanowires on a substrate; forming a solar cell or other electrical devices. The gold nanoparticles replace the silicon substrate on which conventional semiconductor based solar cells are built.

Researchers at the Nies Bohr Institute have determined that sunlight can be concentrated in nanowires due to a resonance effect. This effect can result in more efficient solar cells, allowing more of the energy from the sun to be converted to electricity.

Using light absorbing nanowires embedded in a flexible polymer film is another method being developed to produce low cost flexible solar panels.

Researchers at Lawrence Berkeley have demonstrated an inexpensive process for making solar cells. These solar cells are composed of cadmium sulfide nanowires coated with copper sulfide.

Researchers at Stanford University have grown silicon nanowires on a stainless steel substrate and demonstrated that batteries using these anodes could have up to 10 times the power density of conventional lithium ion batteries. Using silicon nanowires, instead of bulk silicon fixes a problem of the silicon cracking, that has been seen on electrodes using bulk silicon. The cracking is caused because the silicon swells it absorbs lithium ions while being recharged, and contracts as the battery is discharged and the lithium ions leave the silicon. However the researchers found that while the silicon nanowires swell as lithium ions are absorbed during discharge of the battery and contract as the lithium ions leave during recharge of the battery the nanowires do not crack, unlike anodes that used bulk silicon.

Nanowire Applications in the Enviroment

Using silver chloride nanowires as a photocatalysis to decompose organic molecules in polluted water.

Using an electrified filter composed of silver nanowires, carbon nanotubes and cotton to kill bacteria in water.

Using nanowire mats to absorb oil spil

Nanowire Applications in Electronics

Using electrodes made from nanowires that would enable flat panel displays to be flexible as well as thinner than current flat panel displays.

Using nanowires to build transistors without p-n junctions.

Using nanowires made of an alloy of iron and nickel to create dense memory devices. By applying a current magnetized sections along the length of the wire. As the magnetized sections move along the wire, the data is read by a stationary sensor. This method is called race track memory .

Using silver nanowires embedded in a polymer to make conductive layers that can flex, without damaging the conductor.

Sensors using zinc oxide nano-wire detection elements capable of detecting a range of chemical vapors.

Quantum Dots and their Applications

Quantum Dot Applications

 Researchers at Rice University have demonstrated that graphene quantum dots doped with nitrogen can be used as a catalyst to make hydrocarbons from carbor dioxide.

Researchers at Los Alamos National Lab have developed a solar cell that uses a copper indium selenide sulfide quantum dots. Unlike quantum dots containing lead or cadium the copper based quantum dot is non-toxc as well as low cost.

Researchers at the University of Colorado Boulder are investigating the use of quantum dots to treat antibiotic resistant infections.

Using magnetic quantum dots in spintronic semiconductor devices such as memory chips. Spintronic devices are expected to be significantly higher density and lower power consumption because they measure the spin of electronics to determine a 1 or 0, rather than measuring groups of electronics as done in current semiconductor devices.

Researchers are developing  humidity and pressure sensors using graphene quantum dots. These sensors are orginally intented for spaceflight applications because they can function a very low pressure.

Quantum Dots can be used for producing images of cancer tumors. Currently this is used in lab anamials to evaluate the preformance of cancer treatments. 

Quantum dots are being used to produce miniature lasers for use in communications devices. The advantage of these lasers will be high speed data transfer with low power consumption.

Quantum dots can be used in TV or computer displays. Displays using quantum dots should be thinner, lower power than current displays as well as able to be flexible.  

 

Strong Materials | Making Strong Materials with Nanotechnology

The following survey introduces you to nanotechnology techniques being used to produce strong materials:

Researchers at MIT have designed a structure based on graphene shapes called gyroids that they predict will have 10 times the strenght of steel while having only 5% the density of steel.

Researchers at UCLA have demonstated a method to make a strong, lightweight metal by addingceramic silicon carbide nanoparticles to magnesium.

ArcelorMital is producing a kind of steel that contains nanoparticles. This material allows them to make thinner gauge, lighter beams and plates. These steel beams and plates are about same weight as aluminum, but can be produced a lower cost. ArcelorMital is marketing this light weight steel to car manufacturers.

Eagle Windpower has used an epoxy containing carbon nanotubes can be used to produce nanotube-polymer composite windmill blades. This results in a strong but lightweight blade, which makes longer windmill blades practical. These longer blades increase the amount of electricity generated by each windmill.

Researchers at North Carolina State University have developed a method to straighten the carbon nanotubes as the nanotube-polymer composite is being formed. They found that straightening the nanotubes increased the tensile strength of the nanotube-polymer composite, as well as improving the electrical and thermal conductivity.

Avalon Aviation incorporated carbon nanotubes in a carbon fiber composite engine cowling on an aerobatic aircraft to increase the strength to weight ratio. The engine cowling is highly stressed components in this aircraft, adding carbon nanotubes to the composite allowed them to reduce the weight without weakening the component.

Researchers at MIT have developed a method  to add carbon nanotubes aligned perpendicular to the carbon fibers, called 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 composite.

Researchers at North Carolina University have shown how to make magnesium alloy stronger. They introduced nano-spaced stacking faults in the crystalline structure of the alloy. The stacking faults prevent defects in the structure of the alloy from spreading, making the alloy stronger. The researchers believe that the techniques they used to strenghten the alloy can be implemented in existing plants, allowing a fast implementation.

 Researchers at Rensselaer Polytechnic Institute have found that adding graphene to epoxy composites may result in stronger/stiffer components than epoxy composites using a similar weight of carbon nanotubes. Graphene appears to bond better to the polymers in the epoxy, allowing a more effective coupling of the graphene into the structure of the composite. This property could result in the manufacture of components with higher strength-to-weight ratios for such uses as windmill blades or aircraft components.

 

Nanotechnology and Energy

Here are some interesting ways that are being explored using nanotechnology to produce more efficient and cost-effective energy:

Generating steam from sunlight. Researchers have demonstrated that sunlight, concentrated on nanoparticles, can produce steam with high energy efficiency. The "solar steam device" is intended to be used in areas of developing countries without electricity for applications such as purifying water or disinfecting dental instruments. Another research group is developing nanoparticles intended to use sunlight to generate steam for use in running powerplants.

Producing high efficiency light bulbs. A nano-engineered polymer matrix is used in one style of high efficiency light bulbs. The new bulbs have the advantage of being shatterproof and twice the efficiency of compact fluorescence light bulbs. Other researchers developing high efficiency LED's using arrays of nano-sized structures called plasmonic cavities. Another idea under development is toupdate incandescent light bulbs by surrounding the conventional filament with crystalline material that converts some of the waste infrared radiation into visible light.

Increasing the electricity generated by windmills. An epoxy containing carbon nanotubes is being used to make windmill blades. Stronger and lower weight blades are made possible by the use of nanotube-filled epoxy. The resulting longer blades increase the amount of electricity generated by each windmill.

Generating electricity from waste heat. Researchers have used sheets of nanotubes to build thermocells that generate electricity when the sides of the cell are at different temperatures. Thesenanotube sheets could be wrapped around hot pipes, such as the exhaust pipe of your car, to generate electricity from heat that is usually  wasted. 

Storing hydrogen for fuel cell powered cars. Researchers have prepared graphene layers to increase the binding energy of hydrogen to the graphene surface in a fuel tank, resulting in a higher amount of hydrogen storage and therefore a lighter weight fuel tank. Other researchers have demonstrated that sodium borohydride nanoparticles can effectively store hydrogen.

Clothing that generates electricity. Researchers have developed piezoelectric nanofibers that are flexible enough to be woven into clothing. The fibers can turn normal motion into electricity to power your cell phone and other mobile electronic devices.

Reducing friction to reduce the energy consumption. Researchers have developed lubricants using inorganic buckyballs that significantly reduced friction.

Reducing power loss in electric transmission wires. Researchers at Rice University are developing wires containing carbon nanotubes that would have significantly lower resistance than the wires currently used in the electric transmission grid. Richard Smalley envisioned the use of nanotechnology to radically change the electricity distribution grid. Smalley’s concept these upgraded transmission wires, which could transmit electricity thousands of miles with insignificant power losses, with local electricity storage capacity in the form of batteries in each building that could store power for 24 hours use.

Reducing the cost of solar cells. Companies have developed nanotech solar cells that can be manufactured at significantly lower cost than conventional solar cells. Check out our  Nanotechnology in Solar Cells page for the details.

Improving the performance of batteries. Companies are currently developing batteries using nanomaterials. One such battery will be as good as new after sitting on the shelf for decades. Another battery  can be recharged significantly faster than conventional batteries.  Check out ourNanotechnology in Batteries page for details.

Improving the efficiency and reducing the cost of fuel cells. Nanotechnology is being used to reduce the cost of catalysts used in fuel cells. These catalysts produce hydrogen ions from fuel such as methanol. Nanotechnology is also being used to improve the efficiency of membranes used in fuel cells to separate hydrogen ions from other gases, such as oxygen. Check out our Nanotechnology in Fuel Cells page for the details.

Making the production of fuels from raw materials more efficient. Nanotechnology can address the shortage of fossil fuels, such as diesel and gasoline, by making the production of fuels from low grade raw materials economical. Nanotechnology can also be used to increase the mileage of engines and make the production of fuels from normal raw materials more efficient.

Environmental Nanotechnology

Nanotechnology is being used in several applications to improve the environment. This includes cleaning up existing pollution, improving manufacturing methods to reduce the generation of new pollution, and making alternative energy sources more cost effective.

The Application of Nanotechnology to Environmental Issues

Generating less pollution during the manufacture of materials. One example of this is how researchers have demonstrated that the use of silver nanoclusters as catalysts can significantly reduce the polluting byproducts generated in the process used to manufacture propylene oxide. Propylene oxide is used to produce common materials such as plastics, paint, detergents and brake fluid.

Producing solar cells that generate electricity at a competitive cost. Researcher have demonstrated that an array of silicon nanowires embedded in a polymer results in low cost but high efficiency solar cells. This, or other efforts using nanotechnology to improve solar cells, may result in solar cells that generate electricity as cost effectively as coal or oil.

Increasing the electricity generated by windmills. Epoxy containing carbon nanotubes is being used to make windmill blades. The resulting blades are stronger and lower weight and therefore the amount of electricity generated by each windmill is greater.

Cleaning up organic chemicals polluting groundwater. Researchers have shown that iron nanoparticles can be effective in cleaning up organic solvents that are polluting groundwater. The iron nanoparticles disperse throughout the body of water and decompose the organic solvent in place. This method can be more effective and cost significantly less than treatment methods that require the water to be pumped out of the ground.

Cleaning up oil spills. Using photocatalytic copper tungsten oxide nanoparticles to break down oil into biodegradable compounds. The nanoparticles are in a grid that provides high surface area for the reaction, is activated by sunlight and can work in water, making them useful for cleaning up oil spills.

Clearing volatile organic compounds (VOCs) from air. Researchers have demonstrated a  catalyst that breaks down VOCs at room temperature. The catalyst is composed of porous manganese oxide in which gold nanoparticles have been embedded.

Reducing the cost of fuel cells. Changing the spacing of platinum atoms used in a fuel cell increases the catalytic ability of the platinum. This allows the fuel cell to function with about 80% less platinum, significantly reducing the cost of the fuel cell.

Storing hydrogen for fuel cell powered cars. Using graphene layers to increase the binding energy of hydrogen to the graphene surface in a fuel tank results in a higher amount

of hydrogen storage and a lighter weight fuel tank. This could help in the development of practical hydrogen-fueled cars.

Nanotechnology in Medicine - Nanomedicine

Nanotechnology in Medicine Application: Drug Delivery

One application of nanotechnology in medicine currently being developed involves employing nanoparticles to deliver drugs, heat, light or other substances to specific types of cells (such as cancer cells). Particles are engineered so that they are attracted to diseased cells, which allows direct treatment of those cells. This technique reduces damage to healthy cells in the body and allows for earlier detection of disease.

For example, nanoparticles that  deliver chemotherapy drugs directly to cancer cells  are under development. Tests are in progress for targeted delivery of chemotherapy drugs and their final approval for their use with cancer patients is pending. One company, CytImmune has published the results of a Phase 1 Clinical Trial of their first targeted chemotherapy drug and another company, BIND Biosciences, has published preliminary results of a Phase 1 Clinical Trial for their first targeted chemotherapy drug and is proceeding with a Phase 2 Clinical Trial.

Researchers at Georgia State University are using nanoparticles in a influenza vaccine that targets a portion of the virus that is present in all influenza viruses. Their intent is to develop a vaccine that will work on all influenza viruses.

Researchers at the Wyss Institue are testing nanoparticles that release drugs when subjected to sheer force, such as occurs when passing through a section of artery that is mostly blocked by a clot. Lab tests on animals have shown that this method is effective in delivering drugs used to dissolve clots.The  Read more about their study here.

Researchers at the Houston Methodist Research Institute have demonstrated a targeted drug delivery method in mice using silicon nanoparticles that degrade inside a tumor, releasing polymer strands that form a nanoparticle containing the drug to be delivered. This polymer nanoparticle dissolves inside the cancer cell, delivering the drug to the cancer cell.

Researchers at the University of Illinois have demonstated that gelatin nanoparticles can be used to deliver drugs to damaged brain tissue more efficently than standard methods. This has been demonstrated in the lab, the researchers hope that this method will result in more effective drug delivery for brain injuries.

Researchers at MIT are investigating the use of nanoparticles to deliver vaccine.The nanoparticles protect the vaccine, allowing the vaccine time to trigger a stronger immune response as shown in lab tests with mice. Additional work needs to be done to adapt the technique to human patients.

Reserchers are developing a method to release insulin that uses a sponge-like matrix that contains insulin as well as nanocapsules containing an enzyme. When the glucose level rises the nanocapsules release hydrogen ions, which bind to the fibers making up the matrix. The hydrogen ions make the fibers positively charged, repelling each other and creating

openings in the matrix through which insulin is released. So far this has been shown  to be effective in tests with lab mice.

 Researchers are developing a nanoparticle that can be taken orally and pass through the lining of the intestines into the bloodsteam. This should allow drugs that must now be delivered with a shot to be taken in pill form. The researchers have demonstrated the technique with lab mice so far.

Researchers are also developing a nanoparticle to defeat viruses. The nanoparticle does not actually destroy viruses molecules, but delivers an enzyme that prevents the reproduction of viruses molecules in the patients bloodstream.

Nanotechnology in Medicine Application: Therapy Techniques

Researchers have developed "nanosponges" that absorb toxins and remove them from the bloodstream. The nanosponges are polymer nanoparticles coated with a red blood cell membrane. The red blood cell membrane allows the nanosponges to travel freely in the bloodstream and attract the toxins.

Researchers have demonstrated a method to generate sound waves that are powerful, but also tightly focused, that may eventually be used for noninvasive surgery. They use a lens coated with carbon nanotubes to convert light from a laser to focused sound waves. The intent is to develop a method that could blast tumors or other diseased areas without damaging healthy tissue.

Researchers are investigating the use of bismuth nanoparticles to concentrate radiation used in radiation therapy to treat cancer tumors. Initial results indicate that the bismuth nanoparticles would increase the radiation dose to the tumor by 90 percent.

Nanoparticles composed of polyethylene glycol-hydrophilic carbon clusters (PEG-HCC) have been shown to absorb free radicals at a much higher rate than the proteins out body uses for this function. This ability to absorb free radicals may reduce the harm that is caused by the release of free radicals after a brain injury.

Targeted heat therapy is being developed to destroy breast cancer tumors. In this method antibodies that are strongly attracted to proteins produced in one type of breast cancer cell are attached to nanotubes, causing the nanotubes to accumulate at the tumor. Infrared light from a laser is absorbed by the nanotubes and produces heat that incinerates the tumor.

Nanotechnology in Medicine Application: Diagnostic Techniques

Researchers at Worcester Polytechnic Institute are using antibodies attached to carbon nanotubes in chips to detect cancer cells in the blood stream. The researchers believe this method could be used in simple lab tests that could provide early detection of cancer cells in the bloodstream.

Researchers 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 at the University of Michigan are developing a sensor that can detect a very low level of cancer cells, as low as 3 to 5 cancer cells in a one milliliter in a blood sample. They

grow sheets of graphene oxide, on which they attach molecules containing an antibody that attaches to the cancer cells. They then tag the cancer cells with fluorescent molecules to make the cancer cells stand out in a microscope.

Researchers have demonstrated a way to use nanoparticles for early diagnosis of infectious disease. The nanoparticles attach to molecules in the blood stream indicating the start of an infection. When the sample is scanned for Raman scattering the nanoparticles enhance the Raman signal, allowing detection of the molecules indicating an infectious disease at a very early stage.

A test for early detection of kidney damage is being developed. The method uses gold nanorodsfunctionalized to attach to the type of protein generated by damaged kidneys. When protein accumulates on the nanorod the color of the nanorod shifts. The test is designed to be done quickly and inexpensively for early detection of a problem.

Nanotechnology in Medicine Application: Anti-Microbial Techniques

Researchers at the University of Houston are developing a technique to kill bacteria using gold nanoparticles and infrared light. This method may lead to improved cleaning of instruments in hospital settings.

Researchers at the University of Colorado Boulder are investigating the use of quantum dots to treat antibiotic resistant infections.

Researchers at the University of New South Wales are investigating the use of polymer coated iron oxide nanoparticles to treat chronic bacterial infections.

One of the earliest nanomedicine applications was the use of nanocrystalline silver which is  as an antimicrobial agent for the treatment of wounds, as discussed on the Nucryst Pharmaceuticals Corporation website.

A nanoparticle cream has been shown to fight staph infections. The nanoparticles contain nitric oxide gas, which is known to kill bacteria. Studies on mice have shown that using the nanoparticle cream to release nitric oxide gas at the site of staph abscesses significantly reduced the infection.

Burn dressing that is coated with nanocapsules containing antibotics. If a infection starts the harmful bacteria in the wound causes the nanocapsules to break open, releasing the antibotics. This allows much quicker treatment of an infection and reduces the number of times a dressing has to be changed.

A welcome idea in the early study stages is the elimination of bacterial infections in a patient within minutes, instead of delivering treatment with antibiotics over a period of weeks.

Nanotechnology in Medicine Application: Cell Repair

Nanorobots could actually be programmed to repair specific diseased cells, functioning in a similar way to antibodies in our natural healing processes.  Read about design analysis for one such cell repair nanorobot in this article: The Ideal Gene Delivery Vector: Chromallocytes, Cell Repair Nanorobots for Chromosome Repair Therapy

What is MEMS?

MEMS stands for Micro-ElectroMechanical Systems. MEMS techniques allow both electronic circuits and mechanical devices to be manufactured on a silicon chip, similar to the process used for integrated circuits. This allows the construction of items such as sensor chips with built-in electronics that are a fraction of the size that was previously possible. 

MEMS Products

Four devices using MEMS technology have been commercially successful for several years.

MEMS accelerometer chips used to trigger airbags MEMS mirror chips for use in projection screen TVs MEMS inkjet nozzles used in printers MEMS pressure sensors for medical applications

MEMS Products under Development

Several interesting new products and applications are being developed using MEMS.

MEMS - piezoelectric generator being developed for self contained wireless sensors Computer game controller using MEMS accelerometer. Programmable MEMS gyroscope with features that significantly lower the cost of

integrating the gyroscope into industrial equipment. MEMS microphones that are smaller and more resistant to heat than conventional

microphones. MEMS RF switches to reduce power losses in microwave applications. MEMS blood pressure sensor with wireless data transfer that can be implanted in

patients. MEMS oscillators that are smaller and more integrated with electronics circuits than

current quartz oscillators.

Nanotechnology in Manufacturing

Various manufacturers are using nanotechnology to make products with improved capabilities or to reduce their manufacturing cost. This page provides examples of how nanotechnology is helping manufacturers today.

A technique called laser shock imprinting  that forms nanoscale metallic shapes such as gears has been demonstrated by researchers at Prudue University.

Researchers at Northwestern University have developed a desktop nanofabrication tool. The desktop tool uses beam-pen lithography arrays to create nanoscale structures.

Researchers at the University of Pennsylvania have developed a technique to make AFM tips from diamond. The nanoscale diamond tips last much longer than AFM tips made of silicon and the researchers envision these tips being used to etch or deposit material in nano-manufacturing processes.

MesoCoat has developed a nanocomposite coating called CermaClad™ that can be applied to pipes used in the oil industry pipes to provide resistance to corrosion. The process for applying the nanocomposite is faster and can be done at a lower temperature than is possible using conventional methods. The result is the production of lower cost pipes with equivalent corrosion resistance.

Researchers at Rice University have demonstrated that atomically thin sheets of boron nitride can be used as a coating to prevent oxidation. They believe this coating could be used for coating parts that need to be light weight, but work in harsh environments, such as jet engines.

ArcelorMital is producing a kind of steel that contains nanoparticles. This material allows them to make thinner gauge, lighter beams and plates. These steel beams and plates are about same weight as aluminum, but can be produced a lower cost. ArcelorMital is marketing this light weight steel to car manufacturers.

Researchers have produced yarn from carbon nanotubes coated with diamond. They believe this material can be used in thin saw blades that reduce the waste produced when cutting high cost material, such as sawing silicon ingots into wafers for the semiconductor or solar industries.

IMEC and Nantero are developing a memory chip that uses carbon nanotubes. This memory is labeled NRAM for Nanotube-Based Nonvolatile Random Access Memory and is intended to be used in place of high density Flash memory chips.

Nanosolar is building solar cells using semiconductor nanoparticles applied in a low temperature printing process. This process results in lower cost solar cells than conventional high temperature manufacturing processes.

Hewett Packard is working with Hynix Semiconductor to bring a memory device, called a memristor to production. Memristors uses nanowires coated with titanium dioxide and are projected to have better memory density than flash memory.

Intel is producing integrated circuits with feature sizes as small as 22 nm. This process allows Intel to build more computing power into each chip.

St. Croix uses an epoxy resin called NSi that contains silica nanoparticles in making fishing rods that are stronger than rods made with conventional material; but just as lightweight.  

Yonex uses a resin containing buckyballs (fullerenes) to make lightweight badminton racquets with greater hitting power and stability.

Taking the longer view researchers are working on developing a method called molecular manufacturing that may someday make the Star Trek replicator a reality. The gadget these folks envision is called a molecular fabricator; this device would use tiny manipulators to position atoms and molecules to build an object as complex as a desktop computer. As shown in this video, researchers believe that raw materials can be used to reproduce almost any inanimate object using this method.

By building an object atom by atom or molecule by molecule, molecular manufacturing, also called molecular nanotechnology, can produce new materials with improved performance over existing materials. For example, an airplane strut must be very strong, but also lightweight. A molecular fabricator could build the strut atom by atom out of carbon, making a lightweight material that is stronger than a diamond. Remember that a diamond is merely a lattice of carbon atoms held together by bonds between the atoms. By placing carbon atoms, one after the other, in the shape of the strut, such a fabricator could create a diamond-like material that is lightweight and stronger than any metal.

 

Nanotechnology Applications: A Variety of Uses

Nanotechnology Applications in:

MedicineResearchers are developing customized nanoparticles the size of molecules that can deliver drugs directly to diseased cells in your body.  When it's perfected, this method should greatly reduce the damage treatment such as chemotherapy does to a patient's healthy cells.

ElectronicsNanotechnology holds some answers for how we might increase the capabilities of electronics devices while we reduce their weight and power consumption. 

FoodNanotechnology is having an impact on several aspects of food science, from how food is grown to how it is packaged. Companies are developing nanomaterials that will make a difference not only in the taste of food, but also in food safety, and the health benefits that food delivers. 

Fuel CellsNanotechnology is being used to reduce the cost of catalysts used in fuel cells to produce hydrogen ions from fuel such as methanol and to improve the efficiency of membranes used in fuel cells to separate hydrogen ions from other gases such as oxygen.

Solar CellsCompanies have developed nanotech solar cells that can be manufactured at significantly lower cost than conventional solar cells.

BatteriesCompanies are currently developing batteries using nanomaterials. One such battery will be a good as new after sitting on the shelf for decades. Another battery  can be recharged significantly faster than conventional batteries. 

SpaceNanotechnology may hold the key to making space-flight more practical. Advancements in nanomaterials make lightweight spacecraft and a cable for the space elevator possible. By significantly reducing the amount of rocket fuel required, these advances could lower the cost of reaching orbit and traveling in space.

FuelsNanotechnology can address the shortage of fossil fuels such as diesel and gasoline by making the production of fuels from low grade raw materials economical, increasing the mileage of engines, and making the production of fuels from normal raw materials more efficient. 

Better Air QualityNanotechnology can improve the performance of catalysts used to transform vapors escaping from cars or industrial plants into harmless gasses. That's because catalysts made from nanoparticles have a greater surface area to interact with the reacting chemicals than catalysts made from larger particles. The larger surface area allows more chemicals to interact with the catalyst simultaneously, which makes the catalyst more effective. 

Cleaner WaterNanotechnology is being used to develop solutions to three very different problems in water quality. One challenge is the removal of industrial wastes, such as a cleaning solvent called TCE, from groundwater. Nanoparticles can be used to convert the contaminating chemical through a chemical reaction to make it harmless. Studies have shown that this method can be used successfully to reach contaminates dispersed in underground ponds and at much lower cost than methods which require pumping the water out of the ground for treatment.

Chemical SensorsNanotechnology can enable sensors to detect very small amounts of chemical vapors. Various types of detecting elements, such as carbon nanotubes, zinc oxide nanowires or palladium nanoparticles can be used in nanotechnology-based sensors. Because of the small size of nanotubes, nanowires, or nanoparticles, a few gas molecules are sufficient to change the electrical properties of the sensing elements. This allows the detection of a very low concentration of chemical vapors.

Sporting GoodsIf you're a tennis or golf fan, you'll be glad to hear that even sporting goods has wandered into the nano realm. Current nanotechnology applications in the sports arena include increasing the strength of tennis racquets, filling any imperfections in club shaft materials and reducing the rate at which air leaks from tennis balls.

FabricMaking composite fabric with nano-sized particles or fibers allows improvement of fabric properties without a significant increase in weight, thickness, or stiffness as might have been the case with previously-used  techniques.

Nanotechnology in Space

Nanotechnology may hold the key to making space flight more practical. Advancements in nanomaterials make lightweight solar sails and a cable for the space elevator possible. By significantly reducing the amount of rocket fuel required, these advances could lower the cost of reaching orbit and traveling in space. In addition, new materials combined with nanosensors and nanorobots could improve the performance of spaceships, spacesuits, and the equipment used to explore planets and moons, making nanotechnology an important part of the ‘final frontier.’

Space Flight and Nanotechnology: Applications under Development

Researchers are looking into the following applications of nanotechnology in space flight:

Employing materials made from carbon nanotubes to reduce the weight of spaceships like the one shown below while retaining or even increasing the structural strength.

Photo courtesy of NASA

Using carbon nanotubes to make the cable needed for the space elevator, a system which could significantly reduce the cost of sending material into orbit. Nova has a nice video explaining the concepts.

Including layers of bio-nano robots in spacesuits. The outer layer of bio-nano robots would respond to damages to the spacesuit, for example to seal up punctures. An inner layer of bio-nano robots could respond if the astronaut was in trouble, for example by providing drugs in a medical emergency. For more about this see page 30 of this report on Bio-Nano-Machines for Space Applications.

Deploying a network of nanosensors to search large areas of planets such as Mars for traces of water or other chemicals. To read more about this, see page 27 of this report on Bio-Nano-Machines for Space Applications.

Producing t hrusters for spacecraft   that use MEMS devices to accelerate nanoparticles. This should reduce the weight and complexity of thruster systems used for interplanetary missions. One cost-saving feature of these type of thrusters is their ability to draw on more or less of the MEMS devices depending upon the size and thrust requirement of the spacecraft, rather than designing and building different engines for different size spacecraft.

Using carbon nanotubes to build lightweight solar sails that use the pressure of light from the sun reflecting on the mirror-like solar cell to propel a spacecraft. This solves the problem of having to lift enough fuel into orbit to power spacecraft during interplanetary missions.

Working with nanosensors to monitor the levels of trace chemicals in spacecraft to monitor the performance of life support systems.

Spaceflight and Nanotechnology: Research Organizations

The Center for Nanotechnology at NASA Ames is looking at how nanotechnology can be used to reduce the mass, volume, and power consumption of a wide range of spacecraft systems including sensors, communications, navigation, and propulsion systems.

The Johnson Space Center Nano Materials Project is working on nanotube composites with the aim of reducing spacecraft weight. 

The LiftPort Group is dedicated to making the space elevator reality. Their target date is October, 2031.

The Space Nanotechnology Laboratory at MIT is developing high performance instrumentation for use on spaceflights.

Nanotechnology in Electronics: Nanoelectronics

How can nanotechnology improve the capabilities of electronic components?

Nanoelectronics holds some answers for how we might increase the capabilities of electronics devices while we reduce their weight and power consumption. Some of the nanoelectronics areas under development, which you can explore in more detail by following the links provided in the next section, include the following topics.

Improving display screens on electronics devices. This involves reducing power consumption while decreasing the weight and thickness of the screens.

Increasing the density of memory chips. Researchers are developing a type of memory chip with a projected density of one terabyte of memory per square inch or greater.

Reducing the size of transistors used in integrated circuits. One researcher believes it may be possible to "put the power of all of today's present computers in the palm of your hand".

Nanoelectronics: Applications under Development

Researchers are looking into the following nanoelectronics projects:

Cadmium selenide nanocrystals deposited on plastic sheets have been shown to form flexible electronic circuits. Researchers are aiming for a combination of flexibility, a simple fabrication process and low power requirements.

Integrating silicon nanophotonics components into CMOS integrated circuits. This optical technique is intended to provide higher speed data transmission between integrated circuits than is possible with electrical signals.

Researchers at UC Berkeley have demonstrated a low power method to use nanomagnets as switches, like transistors, in electrical circuits. Their method might lead to electrical circuits with much lower power consumption than transistor based circuits.

Researchers at Georgia Tech, the University of Tokyo and Microsoft Research have developed a method to print prototype circuit boards using standard inkjet printers. Silver nanoparticle inkwas used to form the conductive lines needed in circuit boards.

Researchers at Caltech have demonstrated a laser that uses a nanopatterned silicon surfacethat helps produce the light with much tighter frequency control than previously achieved. This may allow much higher data rates for information transmission over fiber optics.

Building transistors from carbon nanotubes to enable minimum transistor dimensions of a few nanometers and developing techniques to manufacture integrated 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.

Developing a lead free solder reliable enough for space missions and other high stress environments using copper nanoparticles.

Using electrodes made from nanowires that would enable flat panel displays to be flexible as well as thinner than current flat panel displays.

Using semiconductor nanowires to build transistors and integrated circuits. Transistors built in single atom thick graphene film to enable very high speed

transistors. Researchers have developed an interesting method of forming PN junctions, a key

component of transistors, in graphene. They patterned the p and n regions in the substrate. When the graphene film was applied to the substrate electrons were either added or taken from the graphene, depending upon the doping of the substrate. The researchers believe that this method reduces the disruption of the graphene lattice  that can occur with other methods.

Combining gold nanoparticles with organic molecules to create a transistor known as a NOMFET (Nanoparticle Organic Memory Field-Effect Transistor).

Using carbon nanotubes to direct electrons to illuminate pixels, resulting in a lightweight, millimeter thick "nanoemmissive" display panel.

Using quantum dots to replace the fluorescent dots used in current displays. Displays using quantum dots should be simpler to make than current displays as well as use less power.

Making integrated circuits with features that can be measured in nanometers (nm), such as the process that allows the production of integrated circuits with 22 nm wide transistor gates.

Using nanosized magnetic rings to make Magnetoresistive Random Access Memory (MRAM)which research has indicated may allow memory density of 400 GB per square inch.

o Researchers have developed lower power, higher density method using nanoscale magnets called magnetoelectric random access memory (MeRAM).

Developing molecular-sized transistors which may allow us to shrink the width of transistor gates to approximately one nm which will significantly increase transistor density in integrated circuits.

Using self-aligning nanostructures to manufacture nanoscale integrated circuits. Using nanowires to build transistors without p-n junctions. Using buckyballs to build dense, low power memory devices.  Using magnetic quantum dots in spintronic semiconductor devices. Spintronic

devices are expected to be significantly higher density and lower power consumption because they measure the spin of electronics to determine a 1 or 0, rather than measuring groups of electronics as done in current semiconductor devices.

Using nanowires made of an alloy of iron and nickel to create dense memory devices. By applying a current magnetized sections along the length of the wire. As the magnetized sections move along the wire, the data is read by a stationary sensor. This method is called race track memory .

Using silver nanowires embedded in a polymer to make conductive layers that can flex, without damaging the conductor.

IMEC and Nantero are developing a memory chip that uses carbon nanotubes. This memory is labeled NRAM for Nanotube-Based Nonvolatile Random Access Memory and is intended to be used in place of high density Flash memory chips.

Researcher have developed an organic nanoglue that forms a nanometer thick film between a computer chip and a heat sink. They report that using this nanoglue

significantly increases the thermal conductance between the computer chip and the heat sink, which could help keep computer chips and other components cool.

Researchers at Georgia Tech, the University of Tokyo and Microsoft Research have developed a method to print prototype circuit boards using standard inkjet printers. Silver nanoparticle inkwas used to form the conductive lines needed in circuit boards.

Nanotechnology in Defence

Military types haven’t failed to notice that nanotechnology could make a big difference to how troops function, travel, and stay safe. The options range from what the well-dressed soldier will wear to methods for making aircraft that can chnage shape while the plane is in flight.

Nanotechnology in Defense: Applications under Developement

The Institute for Soldier Nanotechnologies (ISN) are in the business of developing and taking advantage of nanotechnology to help soldiers survive in battle conditions. A nanobattlesuit is being developed that could be as thin as spandex and contain health monitors and communications equipment. Nanomaterials can also provide strength that far surpasses currently available materials, providing bullet shielding that’s much more effective. These jumpsuit style outfits might even be able to react to and stop biological and chemical attacks. This protection and these devices would be integrated into one suit that would be more efficient and lightweight than current packs. The U.S. Army Natick Soldier Systems Center has published a white paper that discusses how nanotechnology may be used in the "Future Soldier Initiative".

Researchers have worked on aircraft that swing their wings in close for high-speed flight and extend their wings to provide more lift for takeoff and landing. Unfortunately, the hinges that allow the wings to swing add weight, so researchers are developing materials that will need only an electrical voltage to change the shape of aircraft wings and other structures. NASA has developed a carbon nanotube polymer composite that bends when a voltage is applied. This video from NASA gives you an idea of what a future morphing aircraft might look like.

A Mission Adaptive Rotor program, is focused on improving the performance of helicopter rotors. Rotors that can morph would last longer and offer improved performance. These improvements come in part from a reduction in rotor vibration,. The improved performance involves an increase in the amount of weight that the helicopter can carry and an extension of its range.

Shape changing isn’t limited to the skies. The Transformer vehicle being developed by DARPA can travel on roads but is also capable of vertical take-off and landing. The body of the vehicle could morph to grow wings or pull them back in based on whether the vehicle is on land or aloft. As military personnel move around in the TX, they could use the capability to fly to circumvent obstacles, go over rough terrain, and avoid landmines or ambush, while retaining the capability to drive on roads.

Nanotechnology Consumer Products

Nano has already found its way into lots of products you use every day, from clothing to tennis racquets. In fact, if you strolled around your home you’d probably find dozens of products manufactured using some kind of nanotechnology.

A nanoporous material called aerogel that is an excellent insulator, for example insulating the walls of your house would only need about one third the thickness if you used this material instead of conventional insulation.

Knapsacks and briefcases that include flexible, nanoparticle based solar cells to charge your cell phone and other devices on the go.

Skin care products that use nanoparticles to deliver vitamins deeper into the skin.

Sunscreens that use nanoparticles to block UV rays without leaving white residue on the skin.

Lithium ion batteries that use nanoparticle based electrodes powering plug in electric cars.

Flame retardant formed by coating the foam used in furniture with carbon nanofibers.

Fishing rods that use silica nanoparticles to fill spaces between carbon fibers, strengthening the rod without increasing the weight. For more information on how nanotechnology in being used to improve the performance of sporting goods go to ourNanotechnology in Sporting Goods page.

Piezoelectric fibers that could allow clothing to generate electricity through normal motions.

Form fitting clothing made using fabric composed of proteins, this material may stretch as much as 1500 percent from it's original size. For more information on how nanotechnology is being used to improve fabrics go to our Nanotechnology in Fabrics page.

Titanium oxide nanoparticles as part of a film that uses the energy in light to kill bacteria on surfaces. Titanium oxide nanoparticles are called photocatalysts because of their ability to use energy in light to start the chemical reaction that kills the bacteria.

Customizing the properties of particles a few nanometers in diameter to make a better soap.For more information on how nanotechnology is being used to improve cleaning products go to ourNanotechnology in Cleaning Products page.

https://www.nano.gov/nanotech-101

 http://nptel.ac.in/courses/118104008/ 

http://www.understandingnano.com/medicine.html

http://nanotechweb.org/ 

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