Carbon nanotube

Carbon nanotube (452)
Carbon nanotube transistor (19)
Multiwalled carbon nanotube (6)
Nanocarbon (11)
Walled carbon nanotube (23)

Synopsis: Nanotechnology: Nanostructures: Nanotube: Carbon nanotube:

a thin, transparent film made from microscopic tubes called carbon nanotubes (CNTS), aligned parallel to the plane of the film.

gasgetting CNT films to emit sound is not the same as producing good-quality sound over the whole frequency range of human hearing,

So while the CNT speakers might have valuable applications such as sonar#they work perfectly well underwater#it isn't yet clear

One of the ways in which#to improve sound output is to surround the CNT film with a gas that has a lower heat capacity than air,

All things considered, Barnard and colleagues conclude that a high power CNT loudspeaker is feasible, but it won't be simple.

The CNT films will need probably to be enclosed and immersed in xenon, for example, which would pose serious challenges for making robust"wearable#speakers.

which is basically the same stuff as the walls of carbon nanotubes but flattened into sheets.

So one way or another, these forms of nanocarbon look destined to make our isles full of noises.

They can even lay down carbon nanotubes, tiny structures made of linked carbon atoms, and are working to align them to build futuristic circuits, according to Mccarroll.

but they say theye made a breakthrough that could take thermophotovoltaics far beyond where it gone before. mit thermophotovoltaics MIT nanophotonic solar thermophotovoltaic device, with an array of multialled carbon nanotubes as the absorber, a oneimensional silicon/silicon dioxide photonic crystal as the emitter

T) he team inserted a two-layer absorber-emitter device made of novel materials including carbon nanotubes and photonic crystals between the sunlight and the PV cell.

is an array of multiwalled carbon nanotubes, which very efficiently absorbs the light energy and turns it to heat.

and nanotubes By injecting carbon nanotubes into the bloodstream, scientists can use near-infrared lasers to see blood flow in a living animal brain.

or NIR-IIA, involves injecting water-soluble carbon nanotubes into a live mouse bloodstream. The researchers then shine a near-infrared laser over the rodent skull.

Second, injecting carbon nanotubes needs approval for clinical application; the scientists are currently investigating alternative fluorescent agents.

#Handheld terahertz cameras could replace MRI Rice university rightoriginal Studyposted by Mike Williams-Rice on June 11 2014scientists have used carbon nanotubes to create compact terahertz sensors that operate at room temperature.

The scientific community has long been interested in the terahertz properties of carbon nanotubes says Franãois LÃNARD a scientist at Sandia National Laboratories.

and his team have investigated terahertz phenomena in carbon nanotubes but those have focused mainly on the use of one or a bundle of nanotubes.

The thin carbon nanotube film developed by Rice chemist Robert Hauge and graduate student Xiaowei He does not require an antenna

Carbon nanotube thin films are extremely good absorbers of electromagnetic light he explains. In the terahertz range the film a mix of metallic

But that s what we ve achieved with the carbon nanotubes. The research was reported in the journal Nano Letters.

The chip, festooned with tiny carbon nanotubes (engineered segments of carbon that are efficient electrical conductors) and treated with a proprietary polymer

Left to their own devices carbon nanotubes form clumps that are perfectly wrong for turning into the kind of strong conductive fibers needed for projects ranging from nanoscale electronics to macro-scale power grids.

and lead authors Chengmin Jiang a graduate student and Avishek Saha a Rice alumnus starts with negatively charging carbon nanotubes by infusing them with potassium a metal and turning them into a kind of salt known as a polyelectrolyte.

but gave the process a spin with a different preparation so now we re the first to make neat fibers of pure carbon nanotube electrolytes.

and DNA the assembly of nanotechnological components or small organic polymers or the chemical alteration of carbon nanotubes. e need to continue to optimize the system

and nanotubes Stanford university rightoriginal Studyposted by Bjorn Carey-Stanford on August 7 2014by injecting carbon nanotubes into the bloodstream scientists can use near-infrared lasers to see blood flow in a living animal s brain.

or NIR-IIA involves injectingâ water-soluble carbon nanotubes into a live mouse s bloodstream. The researchers then shine a near-infrared laser over the rodent s skull.

Second injecting carbon nanotubes needs approval for clinical application; the scientists are currently investigating alternative fluorescent agents.

The Research center for Exotic Nanocarbons in Japan and the Center for Nanoscale Science at Penn State supported the research u

or PDMS, and carbon nanotubes. HOW IT WORKS When the terahertz light hits the transducer, the nanotubes absorb it,

and solar cells but Pint and Westover are confident that the rules that govern the load-bearing character of their design will carry over to other materials such as carbon nanotubes and lightweight porous metals like aluminum.

and use that energy to fuel autonomous walking along the carbon nanotube trackchoi says. The core is made of an enzyme that cleaves off part of a strand of RNA.

and medical devices to structural components for the automotive civil and aerospace industries. he cellulose nanocrystals represent a potential green alternative to carbon nanotubes for reinforcing materials such as polymers and concrete.

but graphene nanoribbons (GNRS) unzipped from multiwalled carbon nanotubes in a chemical process invented by the Tour group in 2009 do the job nicely he says.

Tour s breakthrough nzippingtechnique for turning multiwalled carbon nanotubes into GNRS first revealed in Nature in 2009 has been licensed for industrial production. hese are being produced in bulk

#Does this carbon nanotube computer spell the end for silicon? Stanford university rightoriginal Studyposted by Tom Abate-Stanford on September 27 2013engineers have built a basic computer using carbon nanotubes a success that points to a potentially faster more efficient alternative to silicon chips.

The achievement is reported in an article on the cover of the journal Nature. eople have been talking about a new era of carbon nanotube electronics moving beyond siliconsays Subhasish Mitra an electrical engineer

and computer scientist at Stanford university who co-led the work. ut there have been few demonstrations of complete digital systems using this exciting technology.

Here is the proof. xperts say the achievement will galvanize efforts to find successors to silicon chips which could soon encounter physical limits that might prevent them from delivering smaller faster cheaper electronic devices. arbon nanotubes CNTS have long been considered as a potential successor to the silicon transistorsays Professor

But until now it hasn t been clear that CNTS a semiconductor material could fulfill those expectations. here is no question that this will get the attention of researchers in the semiconductor community

Mihail Roco a senior advisor for nanotechnology at the National Science Foundation called the work n important scientific breakthrough. t was roughly 15 years ago that carbon nanotubes were fashioned first into transistors the on-off switches

But a bedeviling array of imperfections in these carbon nanotubes has frustrated long efforts to build complex circuits using CNTS.

team has made to this worldwide effort. irst they put in place a process for fabricating CNT-based circuitsde Micheli says. econd they built a simple

but effective circuit that shows that computation is doable using CNTS. s Mitra says: t s not just about the CNT COMPUTER.

It s about a change in directions that shows you can build something real using nanotechnologies that move beyond silicon

He called the Stanford work major benchmarkin moving CNTS toward practical use. CNTS are long chains of carbon atoms that are extremely efficient at conducting and controlling electricity.

They are so thinâ##thousands of CNTS could fit side by side in a human hairâ##that it takes very little energy to switch them off according to Wong a co-author of the paper. hink of it as stepping on a garden hosewong explains. he thinner the hose the easier it is to shut off the flow. n theory this combination

of efficient conductivity and low-power switching make carbon nanotubes excellent candidates to serve as electronic transistors. NTS could take us at least an order of magnitude in performance beyond where you can project silicon could take uswong said.

But inherent imperfections have stood in the way of putting this promising material to practical use.

First CNTS do not necessarily grow in neat parallel lines as chipmakers would like. Over time researchers have devised tricks to grow 99.5 percent of CNTS in straight lines.

But with billions of nanotubes on a chip even a tiny degree of misaligned tubes could cause errors

A second type of imperfection has stymied also CNT technology. Depending on how the CNTS grow a fraction of these carbon nanotubes can end up behaving like metallic wires that always conduct electricity instead of acting like semiconductors that can be switched off.

Since mass production is the eventual goal researchers had to find ways to deal with misaligned

and/or metallic CNTS without having to hunt for them like needles in a haystack. e needed a way to design circuits without having to look for imperfections

or metallic nanotubes the Stanford team switched off all the good CNTS. Then they pumped the semiconductor circuit full of electricity.

This sophisticated technique eliminated the metallic CNTS in the circuit. Bypassing the misaligned nanotubes required even greater subtlety.

whether or where CNTS might be askew. his imperfections-immune design technique makes this discovery truly exemplarysays Sankar Basu a program director at the National Science Foundation.

Their CNT COMPUTER performed tasks such as counting and number sorting. It runs a basic operating system that allows it to swap between these processes.

In a demonstration of its potential the researchers also showed that the CNT COMPUTER could run MIPS a commercial instruction set developed in the early 1980s by then Stanford engineering professor and now university President John Hennessy.

Though it could take years to mature the Stanford approach points toward the possibility of industrial-scale production of carbon nanotube semiconductors according to Naresh Shanbhag a professor at the University of Illinois at Urbana-Champaign

and director of SONIC a consortium of next-generation chip design research. he Wong/Mitra paper demonstrates the promise of CNTS in designing complex computing systemsshanbhag says adding that this will motivate researchers elsewhere toward greater efforts in chip design

beyond silicon. hese are initial necessary steps in taking carbon nanotubes from the chemistry lab to a real environmentsays Supratik Guha director of physical sciences for IBM s Thomas J. Watson Research center

and a world leader in CNT research. The National Science Foundation SONIC the Stanford Graduate Fellowship and the Hertz Foundation Fellowship funded the work.

since graphene (and its cousin material, carbon nanotubes) is the only material with the high strength-to-weight ratio required for this kind of hypothetical application.

each sensor utilizes an array of tens of thousands of carbon nanotubes, which have had copper atoms attached to them.

#Explosives and Pesticides Can Be detected by Using Bee venom Scientists from MIT have discovered that by coating carbon nanotubes in bee venom,

##Researchers at#USC s Viterbi School of Engineeringhave created a#functioning synapse#using neurons made from carbon nanotubes.

A project at IBM is now aiming to have built transistors using carbon nanotubes ready to take over from silicon transistors soon after 2020.

In 1998, researchers at IBM made one of the first working carbon nanotube transistors. And now after more than a decade of research, IBM is the first major company to commit to getting the technology ready for commercialization.

and unlike carbon nanotubes, they don t behave similarly to silicon transistors, says Hannon. Subhasish Mitra, a professor who worked on the project.

We now know that you can build something useful with carbon nanotubes, he says. The question is,

when they reinforced the polymer with carbon nanotubes, it became 50 percent stronger. IBM Research's James Hedrick, who co-authored the new paper,

Baughman has made artificial muscles out of carbon nanotube yarns before but those are much more expensive and complicated to make.

The new muscles contract to about 50 percent of their length compared with carbon nanotubes which contract to only about 10 percent their initial length he said.

what the paper describes as highly tunable composite films of carbon nanotubes and silver nanoparticles that are patterned on high-aspect-ratio elastic fibers.

A handful work at room temperature (by using carbon nanotubes to detect electrons for example2), but they cannot operate in water#a serious obstacle to using such devices in living organisms.

But in the new work they instead used carbon nanotubes atom-thick sheets of carbon rolled into cylinders grown on the slopes of the emitters like trees on a mountainside.

Grossman team tried attaching the molecules to carbon nanotubes (CNTS), but t incredibly hard to get these molecules packed onto a CNT in that kind of close packing,

Kucharski says. But then they found a big surprise: Even though the best they could achieve was a packing density less than half of

called azobenzene, protrude from the sides of the CNTS like the teeth of a comb.

they were interleaved with azobenzene molecules attached to adjacent CNTS. The net result: The molecules were actually much closer to each other than expected.

The interactions between azobenzene molecules on neighboring CNTS make the material work, Kucharski says. While previous modeling showed that the packing of azobenzenes on the same CNT would provide only a 30 percent increase in energy storage,

the experiments observed a 200 percent increase. New simulations confirmed that the effects of the packing between neighboring CNTS,

as opposed to on a single CNT, explain the significantly larger enhancements. This realization, Grossman says,

opens up a wide range of possible materials for optimizing heat storage. Instead of searching for specific photoswitching molecules

The adoption of carbon nanotubes to increase materialsenergy storage density is lever, says Yosuke Kanai, an assistant professor of chemistry at the University of North carolina who was involved not in this work.

In a new Nature Materials paper, the researchers report boosting plantsability to capture light energy by 30 percent by embedding carbon nanotubes in the chloroplast,

Using another type of carbon nanotube, they also modified plants to detect the gas nitric oxide. Together

the researchers also embedded semiconducting carbon nanotubes, coated in negatively charged DNA, into the chloroplasts. Plants typically make use of only about 10 percent of the sunlight available to them,

but carbon nanotubes could act as artificial antennae that allow chloroplasts to capture wavelengths of light not in their normal range, such as ultraviolet, green,

With carbon nanotubes appearing to act as a rosthetic photoabsorber photosynthetic activity measured by the rate of electron flow through the thylakoid membranes was 49 percent greater than that in isolated chloroplasts without embedded nanotubes.

When nanoceria and carbon nanotubes were delivered together, the chloroplasts remained active for a few extra hours. The researchers then turned to living plants

Lean green machines The researchers also showed that they could turn Arabidopsis thaliana plants into chemical sensors by delivering carbon nanotubes that detect the gas nitric oxide,

Strano lab has developed previously carbon nanotube sensors for many different chemicals, including hydrogen peroxide, the explosive TNT, and the nerve gas sarin.

it alters the tube fluorescence. e could someday use these carbon nanotubes to make sensors that detect in real time, at the single-particle level,

To create these ynthetic antibodies, the researchers used carbon nanotubes hollow, nanometer-thick cylinders made of carbon that naturally fluoresce

the carbon nanotube fluorescence brightens or dims. The MIT team found that they could create novel sensors by coating the nanotubes with specifically designed amphiphilic polymers polymers that are drawn to both oil and water, like soap.

Moreover, this approach can provide a more durable alternative to coating sensors such as carbon nanotubes with actual antibodies,

Their approach takes advantage of a phenomenon that occurs when certain types of polymers bind to a carbon nanotube.

when the polymers are exposed to carbon nanotubes, the hydrophobic regions latch onto the tubes like anchors

and alter the carbon nanotube fluorescence. Molecular interactions What is unique about this approach, the researchers say,

using data generated from a new type of microscope that Landry built to image the interactions between the carbon nanotube coronas

Among nanomaterials, carbon-based nanoparticles such as carbon nanotubes and graphene have shown promising results, but they suffer from relatively low electrical conductivity,

Other groups have made similar supercapacitors using carbon nanotubes or other materials, but the niobium yarns are stronger and 100 times more conductive.

Overall, niobium-based supercapacitors can store up to five times as much power in a given volume as carbon nanotube versions.

#Carbon nanotube finding could lead to flexible electronics with longer battery life University of Wisconsin-Madison materials engineers have made a significant leap toward creating higher-performance electronics with improved battery lifend the ability

the team has reported the highest-performing carbon nanotube transistors ever demonstrated. In addition to paving the way for improved consumer electronics,

000 times better and a conductance that's 100 times better than previous state-of-the-art carbon nanotube transistors."

"Carbon nanotubes are very strong and very flexible, so they could also be used to make flexible displays

"Carbon nanotubes are single atomic sheets of carbon rolled up into a tube. As some of the best electrical conductors ever discovered, carbon nanotubes have long been recognized as a promising material for next-generation transistors,

which are semiconductor devices that can act like an on-off switch for current or amplify current. This forms the foundation of an electronic device.

However, researchers have struggled to isolate purely semiconducting carbon nanotubes, which are crucial, because metallic nanotube impurities act like copper wires and"short"the device.

these two challenges have limited the development of high-performance carbon nanotube transistors. Building on more than two decades of carbon nanotube research in the field,

the UW-Madison team drew on cutting-edge technologies that use polymers to selectively sort out the semiconducting nanotubes,

achieving a solution of ultra-high-purity semiconducting carbon nanotubes. Previous techniques to align the nanotubes resulted in less than-desirable packing density,

In that technique, researchers exploited a self-assembly phenomenon triggered by rapidly evaporating a carbon nanotube solution.

The team's most recent advance also brings the field closer to realizing carbon nanotube transistors as a feasible replacement for silicon transistors in computer chips and in high-frequency communication devices,

"With these results, we've really made a leap in carbon nanotube transistors. Our carbon nanotube transistors are an order of magnitude better in conductance than the best thin film transistor technologies currently being used commercially

while still switching on and off like a transistor is supposed to function.""The researchers have patented their technology through the Wisconsin Alumni Research Foundation

Two studies Complement activation by carbon nanotubes and its influence on the phagocytosis and cytokine response by macrophages and Complement deposition on nanoparticles can modulate immune responses by macrophage B

and T cells found that carbon nanotubes (CNTS) triggered a chain reaction in the complement system which is part of the innate immune system

The interaction between CNTS and C1q (a starter-protein for complement) was anti-inflammatory. This suggests that either coating nanoparticles

if the binding between complement proteins and CNTS was direct or indirect. However changing the surfaces of CNTS affected how likely the complement system was to be activated and in what way.

Using the data from this study carbon nanoparticles coated with genetically-engineered proteins are being used to target glioblastoma the most aggressive form of brain tumour.

The researchers combined semiconductor nanorods and carbon nanotubes to create a wireless light-sensitive flexible film that could potentially replace a damaged retina.

We hope our carbon nanotube and semiconductor nanorod film will serve as a compact replacement for damaged retinas.

"The breakthrough extends a stream of nanotechnology research at Rice that began with chemist Robert Hauge's 2009 invention of a"flying carpet"technique to grow very long bundles of aligned carbon nanotubes.

To increase the nanowires'surface area Nath can make them hollow in the middle much like carbon nanotubes found in optics and electronics.

Adrian Bachtold, together with Marc Dykman (Michigan University), report on an experiment in which a carbon nanotube mechanical resonator exhibits quality factors of up to 5 million,

Nowadays, carbon nanotube mechanical resonators are in demand because of their extremely small size and their outstanding capability of sensing objects at the nanoscale.

Like a guitar string or a tightrope, a carbon nanotube resonator consists of a tiny, vibrating bridge-like (string) structure with typical dimensions of 1#m in length and 1nm in diameter.

#Better bomb-sniffing technology with new detector material University of Utah engineers have developed a new type of carbon nanotube material for handheld sensors that will be quicker

A carbon nanotube is a cylindrical material that is a hexagonal or six-sided array of carbon atoms rolled up into a tube.

Carbon nanotubes are known for their strength and high electrical conductivity and are used in products from baseball bats and other sports equipment to lithium-ion batteries and touchscreen computer displays.

Zang and his team found a way to break up bundles of the carbon nanotubes with a polymer

the Utah carbon nanotube technology has four advantages s

#A quantum leap in nanoparticle efficiency (Phys. org) New research has unlocked the secrets of efficiency in nanomaterials that is materials with very tiny particles

The National Science Foundation (NSF)- funded scientist theorized correctly that he could adapt it to separate carbon nanotubes rolled sheets of graphene (a single atomic layer of hexagonally bonded carbon atoms) long recognized for their potential applications in computers

The carbon nanotubes separation process which Hersam developed begins with a centrifuge tube. Into that we load a water based solution and introduce an additive

We then load the carbon nanotubes and put it into the centrifuge which drives the nanotubes through the gradient.

Carbon nanotubes are highly resilient Hersam says. That allows us to integrate electronics on flexible substrates like clothing shoes and wrist bands for real time monitoring of biomedical diagnostics and athletic performance.

Breakthrough for carbon nanotube solar cell l

#See-through one-atom-thick carbon electrodes powerful tool to study brain disorders Researchers from the Perelman School of medicine and School of engineering at the University of Pennsylvania and The Children's Hospital of Philadelphia have used graphene

The Center for Neuroengineering and Therapeutics (CNT) under the leadership of senior author Brian Litt Phd has solved this problem with the development of a completely transparent graphene microelectrode that allows for simultaneous optical imaging

Kuzum emphasizes that the transparent graphene microelectrode technology was achieved through an interdisciplinary effort of CNT and the departments of Neuroscience Pediatrics and Materials science at Penn and the division of Neurology at CHOP.

The combination of nanocarbon and sulfur is effective at overcoming the insulating nature of sulfur for lithium sulfur batteries."

"Due to excellent electrical conductivity, mechanical strength and chemical stability, nanocarbon materials have played an essential role in the area of advanced energy storage,

Recently, scientists from Tsinghua University have created a freestanding carbon nanotube paper electrode with high sulfur loading for lithium-sulfur batteries.

"We select carbon nanotube (CNT) as the building block",Qiang told Phys. org, "CNTS are one of the most efficient and effective conductive fillers for electrode.

We selected short multi-walled CNTS (MWCNTS) with lengths of 10-50 m as the shortrange electrical conductive network to support sulfur,

as well as super long CNTS with lengths of 1000-2000 m from vertically aligned CNTS (VACNTS) as both long-range conductive networks and inter-penetrated binders for the hierarchical freestanding paper electrode.""

""We develop a bottom-up routine in which sulfur was dispersed firstly well into the MWCNT network to obtain MWCNT@S building blocks

and then MWCNT@S and VACNTS were assembled into macro-CNT-S films via the dispersion in ethanol followed by vacuum filtration",Zhe Yuan,

"Such sulfur electrodes with hierarchical CNT scaffolds can accommodate over 5 to 10 times the sulfur species compared with conventional electrodes on metal foil current collectors

"The areal capacity can be increased further to 15.1 mah cm-2 by stacking three CNT-S paper electrodes, with an areal sulfur loading of 17.3 mg cm-2 as the cathode in a Li

which is also favorable for graphene, CNT-graphene, CNTMETAL oxide based flexible electrodes, "Qiang said."

Brighter new energy saving flat panel lights based on carbon nanotubes Even as the 2014 Nobel prize in Physics has enshrined light emitting diodes (LEDS) as the single most significant and disruptive energy-efficient lighting solution of today scientists

Electronics based on carbon especially carbon nanotubes (CNTS) are emerging as successors to silicon for making semiconductor materials.

Scientists from Tohoku University in Japan have developed a new type of energy-efficient flat light source based on carbon nanotubes with very low power consumption of around 0. 1 Watt for every hour's operation

and optimization of the device which is based on a phosphor screen and single-walled carbon nanotubes as electrodes in a diode structure.

They assembled the device from a mixture liquid containing highly crystalline single-walled carbon nanotubes dispersed in an organic solvent mixed with a soap-like chemical known as a surfactant.

The new devices have luminescence systems that function more like cathode ray tubes with carbon nanotubes acting as cathodes

We have found that a cathode with highly crystalline single-walled carbon nanotubes and an anode with the improved phosphor screen in our diode structure obtained no flicker field emission current and good brightness homogeneity Shimoi said.

In recent years carbon nanotubes have emerged as a promising material of electron field emitters owing to their nanoscale needle shape and extraordinary properties of chemical stability thermal conductivity and mechanical strength.

Highly crystalline single-walled carbon nanotubes (HCSWCNT) have nearly zero defects in the carbon network on the surface Shimoi explained.

The resistance of cathode electrode with highly crystalline single-walled carbon nanotube is very low. Thus the new flat-panel device has compared smaller energy loss with other current lighting devices

Many researchers have attempted to construct light sources with carbon nanotubes as field emitter Shimoi said. But nobody has developed an equivalent and simpler lighting device.

But in the new work they instead used carbon nanotubes atom-thick sheets of carbon rolled into cylinders grown on the slopes of the emitters like trees on a mountainside.

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