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.
Researchers have struggled also to control the placement and alignment of nanotubes. Until now 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,
or how close the nanotubes are to one another when they are assembled in a film. However, the UW-Madison researchers pioneered a new technique,
called floating evaporative self-assembly, or FESA, which they described earlier in 2014 in the ACS journal Langmuir.
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,
which are rapidly approaching their physical scaling and performance limits.""This is not an incremental improvement in performance,
"Arnold says.""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
and have begun working with companies to accelerate the technology transfer to industry t
#A new step towards using graphene in electronic applications A team of the University of Berkeley
and the Centre for Materials Physics (CSIC-UPV/EHU) has managed with atomic precision to create nanostructures combining graphene ribbons of varying widths.
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.
#Scientists use'smallest possible diamonds'to form ultra-thin nanothreads For the first time scientists have discovered how to produce ultra-thin diamond nanothreads that promise extraordinary properties including strength and stiffness greater than that of today's strongest nanotubes
Scientists create multifunctional nanotubes using nontoxic materials A doctoral student in materials science at Technische Universitat Darmstadt is making multifunctional nanotubes of goldith the help of Vitamin c and other harmless substances.
The doctoral student in the research group of Professor Wolfgang Ensinger in the Department of Material Analysis is working on making nanotubes of gold.
The metal on the walls of the channels adopts the shape of nanotubes; the film is dissolved then.
The gold nanotubes are thus several hundred times finer than a human hair. Their wall thickness depends both on the duration of precipitation and on the gold concentration of the original solution.
the result is-depending on the experimental conditions-a collection of individual nanotubes or an array of hundreds of thousands of interconnected tubes.
"With 1 gram of gold, we could make a nanotube for literally every person on earth."
Ensinger's team has tested already successfully one use of the gold nanotubes: they are suitable for building sensors to measure hydrogen peroxide.
The gold nanotubes conduct electricity especially well due to their one-dimensional structure. In addition, they are relatively long
For example, they are thinking about also using the nanotubes to measure blood sugar.""A subcutaneous sensor could save diabetes patients from having to constantly prick their fingers"thinks Ensinger.
#Nanotubes may restore sight to blind retinas The aging process affects everything from cardiovascular function to memory to sexuality.
The researchers combined semiconductor nanorods and carbon nanotubes to create a wireless light-sensitive flexible film that could potentially replace a damaged retina.
or older who have damage to a specific part of the retina will stand to benefit from the nanotube device
We hope our carbon nanotube and semiconductor nanorod film will serve as a compact replacement for damaged retinas.
#Graphene/nanotube hybrid benefits flexible solar cells Rice university scientists have invented a novel cathode that may make cheap, flexible dye-sensitized solar cells practical.
from nanotubes that are bonded seamlessly to graphene and replaces the expensive and brittle platinum-based materials often used in earlier versions.
"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.
In his process, the nanotubes remained attached to the surface substrate but pushed the catalyst up as they grew.
The graphene/nanotube hybrid came along two years ago. Dubbed"James'bond"in honor of its inventor, Rice chemist James Tour, the hybrid features a seamless transition from graphene to nanotube.
The graphene base is grown via chemical vapor deposition and a catalyst is arranged in a pattern on top.
which lifts off and allows the new nanotubes to grow. When the nanotubes stop growing,
the remaining catalyst (the"carpet")acts as a cap and keeps the nanotubes from tangling.
The hybrid material solves two issues that have held back commercial application of dye-sensitized solar cells,
First, the graphene and nanotubes are grown directly onto the nickel substrate that serves as an electrode,
With no interruption in the atomic bonds between nanotubes and graphene, the material's entire area, inside and out, becomes one large surface.
Lou's lab built and tested solar cells with nanotube forests of varying lengths The shortest,
Other nanotube samples were grown for an hour and measured about 100-150 microns. When combined with an iodide salt-based electrolyte and an anode of flexible indium tin oxide,
Tests found that solar cells made from the longest nanotubes produced the best results and topped out at nearly 18 milliamps of current per square centimeter
a tiny hole in a ceramic sheet that holds electrolyte to carry the electrical charge between nanotube electrodes at either end.
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,
30 times better than the best quality factors measured in nanotubes to date. Imagine that the host of a dinner party tries to get his guests'attention by giving a single tap of his oyster spoon on his crystal glass.
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.
and because of this trend it was unthinkable that nanotubes could exhibit giant quality factors. The giant quality factors that ICFO researchers have measured have not been observed before in nanotube resonators mainly
because their vibrational states are extremely fragile and easily perturbed when measured. The values detected by the team of scientists was achieved through the use of an ultra-clean nanotube at cryostat temperatures of 30mk(-273.12 Celsius-colder than the temperature of outerspace!
and by employing an ultra-low noise method to detect minuscule vibrations quickly while reducing as much as possible the electrostatic noise.
since"nanotube resonators are enormously sensitive to surrounding electrical charges that fluctuate constantly. This stormy environment strongly affects our ability to capture the intrinsic behavior of nanotube resonators.
For this reason, we had to take a very large number of snapshots of the nanotube's mechanical behavior.
Only a few of these snapshots captured the intrinsic nature of the nanotube's dynamics, when the storm momentarily relented.
During these short quiet moments, the nanotube revealed its ultra-high quality factor to us"."With the discovery of such high quality factors from this study, ICFO scientists have opened a whole new realm of possibilities for sensing applications,
and quantum experiments. For instance, nanotube resonators might be used to detect individual nuclear spins, which would be an important step towards magnetic resonance imaging (MRI) with a spatial resolution at the atomic level.
For the moment, Adrian Bachtold comments that"achieving MRI at the atomic level would be fantastic. But, for this, we would first have to solve various technological problems that are extremely challenging. n
#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.
The new kind of nanotubes also could lead to flexible solar panels that can be rolled up and stored or even"painted"on clothing such as a jacket,
Zang and his team found a way to break up bundles of the carbon nanotubes with a polymer
they alter the electrical current through the nanotube materials, signaling the presence of any of those substances,
and monitor the current through the nanotube,"says Zang, a professor with USTAR, the Utah Science Technology and Research economic development initiative."
or toxic chemicals caught by the nanotube, you will see an increase or decrease in the current."
"By modifying the surface of the nanotubes with a polymer, the material can be tuned to detect any of more than a dozen explosives,
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.
The nanotubes move through the gradient until their density matches that of the gradient. The result is that the nanotubes form separated bands in the centrifuge tube by density.
Since the density of the nanotube is a function of its diameter this method allows separation by diameter.
One property that distinguishes these materials from traditional semiconductors like silicon is that they are mechanically flexible.
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.
These materials have the right combination of properties to realize wearable electronics. He and his colleagues also are working on energy technologies such as solar cells
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
Under a strong electric field the cathode emits tight high-speed beams of electrons through its sharp nanotube tips a phenomenon called field emission.
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.
and height of the nanotubes the researchers were able to achieve a fluid flow that enabled an operating ion current at very near the theoretical limit.
To control the nanotubes'growth the researchers first cover the emitter array with an ultrathin catalyst film
The nanotubes grow up under the catalyst particles which sit atop them until the catalyst degrades.
Using their nanotube forest they're able to get the devices to operate in pure ion mode
#New nanomaterial introduced into electrical machines Lappeenranta University of Technology in Finland has constructed the world's first prototype electrical motor using carbon nanotube yarn in the motor windings.
carbon nanotube yarn. The presently most electrically conductive carbon nanotube yarn replaces usual copper wires in the windings.
The motor prototype is built by the LUT Electrical engineering group as a start towards lightweight efficient electric drives.
In the near future carbon nanotube fibers have potential to significantly enhance the performance and energy efficiency of electrical machines.
The best carbon nanotubes (CNTS) have demonstrated conductivities far beyond those of the best metals. Thus future windings made of CNTS may have a double conductivity compared with the present-day copper windings.
In order to make CNTS easy to manipulate they are spun to form multifiber yarn. If we keep the electrical machine design parameters unchanged and only replace copper with future carbon nanotube wires it is possible to reduce the Joule losses in the windings to half of the present-day machine losses.
Carbon nanotube wires are significantly lighter than copper and also environmentally friendlier. Therefore replacing copper with nanotube wires should significantly reduce the CO2 EMISSIONS related to the manufacturing
and operating of electrical machines. Furthermore the machine dimensions and masses could be reduced. The motors could also be operated in significantly higher temperatures than the present ones says Professor Juha Pyrh nen who has led the design of the prototype at LUT.
No definite upper limit for the conductivity Traditionally the windings in electrical machines are made of copper which has the second best conductivity of metals at room temperature.
Despite the high conductivity of copper a large proportion of the electrical machine losses occur in the copper windings.
The carbon nanotube yarn does not have a definite upper limit for conductivity (e g. values of 100 MS/m have already been measured.
The prototype motor uses carbon nanotube yarns spun and converted into an isolated tape by a Japanese-Dutch company Teijin Aramid
We expect that in the future the conductivity of carbon nanotube yarns could be even three times the practical conductivity of copper in electrical machines.
Carbon nanotube fibers outperform coppe e
#New absorber will lead to better biosensors Biological sensors or biosensors are like technological canaries in the coalmine.
#Nanoparticles accumulate quickly in wetland sediment (Phys. org) A Duke university team has found that nanoparticles called single-walled carbon nanotubes accumulate quickly in the bottom sediments of an experimental wetland setting an action they say could indirectly damage the aquatic food chain.
But the researchers warn that based on their previous research the tendency for the nanotubes to accumulate in sediment could indirectly damage the aquatic food chain in the long term
Carbon nanotubes are rapidly becoming more common because of their usefulness in nanoelectric devices composite materials and biomedicine.
Ferguson and his colleagues dosed the mesocosms with single-walled carbon nanotubes and measured their concentrations in the water soil and living organisms during the course of a year.
and the animals that eat them Previous research has shown that carbon nanotubes take a long time to degrade through natural processes
whether or not these pollutants can be stripped away from the carbon nanotubes by these animals'digestive systems after being ingested continued Ferguson.
Biodistribution of carbon nanotubes in the body More information: Fate of single walled carbon nanotubes in wetland ecosystems. Schierz A. Espinasse B. Wiesner M. R. Bisesi J. H. Sabo-Attwood T. Ferguson P. L. Environmental science:
Nano Sept. 2014. DOI: 10.1039/c4en00063 3
#All directions are created not equal for nanoscale heat sources Thermal considerations are rapidly becoming one of the most serious design constraints in microelectronics, especially on submicron scale lengths.
#Nanotube cathode beats large pricey laser Scientists are a step closer to building an intense electron beam source without a laser.
Using the High-Brightness Electron Source Lab at DOE's Fermi National Accelerator Laboratory a team led by scientist Luigi Faillace of Radiabeam Technologies is testing a carbon nanotube cathode about the size of a nickel
Tests with the nanotube cathode have produced beam currents a thousand to a million times greater than the one generated with a large pricey laser system.
While carbon nanotube cathodes have been studied extensively in academia Fermilab is the first facility to test the technology within a full-scale setting.
The exceptional strength of carbon nanotubes prevents the cathode from being destroyed. Traditionally accelerator scientists use lasers to strike cathodes
The tested nanotube cathode requires no laser: it only needs the electric field already generated by an accelerator to siphon the electrons off a process dubbed field emission n
and carbon nanotubes is one of the most promising novel technology for producing inexpensive printed solar cells.
Physicists at Umeå University have discovered that one can reduce the number of carbon nanotubes in the device by more than 100 times
Carbon nanotubes are more and more attractive for use in solar cells as a replacement for silicon. They can be mixed in a semiconducting polymer
and the nanotubes have outstanding electrical conductivity, and they can effectively separate and transport electrical charges generated from solar energy.
if carbon nanotubes are connected to each other in a controlled manner to form complex nanosized networks, one can achieve significantly higher charge transport
Previous studies have reported that there is a percolation threshold for the amount of carbon nanotubes necessary to transport efficiently electric charges in a device.
and charge transport at very low nanotube loadings, thereby strongly reducing materials costs o
#Scientists improve microscopic batteries with homebuilt imaging analysis (Phys. org) In a rare case of having their cake
#Nanotubes help healing hearts keep the beat (Phys. org) Carbon nanotubes serve as bridges that allow electrical signals to pass unhindered through new pediatric heart-defect patches invented at Rice university and Texas Children's Hospital.
and chemical engineer and chemist Matteo Pasquali created the patches infused with conductive single-walled carbon nanotubes.
The nanotubes overcome a limitation of current patches in which pore walls hinder the transfer of electrical signals between cardiomyocytes the heart muscle's beating cells
Nanotubes can fix that and Jacot who has a joint appointment at Rice and Texas Children's took advantage of the surrounding collaborative research environment.
We thought nanotubes could be integrated easily. Nanotubes enhance the electrical coupling between cells that invade the patch helping them keep up with the heart's steady beat.
When cells first populate a patch their connections are compared immature with native tissue Jacot said.
but the nanotubes forge a path around the obstacles. Jacot said the relatively low concentration of nanotubes 67 parts per million in the patches that tested best is key.
Earlier attempts to use nanotubes in heart patches employed much higher quantities and different methods of dispersing them.
Jacot's lab found a component they were already using in their patches#chitosan#keeps the nanotubes spread out.
Chitosan is amphiphilic meaning it has hydrophobic and hydrophilic portions so it can associate with nanotubes (which are hydrophobic)
and keep them from clumping. That's what allows us to use much lower concentrations than others have tried.
Because the toxicity of carbon nanotubes in biological applications remains an open question Pasquali said the fewer one uses the better.
and get to it with the fewest nanotubes possible he said. We can do this if we control dispersion well and use high-quality nanotubes.
The patches start as a liquid. When nanotubes are added the mixture is shaken through sonication to disperse the tubes
which would otherwise clump due to Van der waals attraction. Clumping may have been an issue for experiments that used higher nanotube concentrations Pasquali said.
The material is spun in a centrifuge to eliminate stray clumps and formed into thin fingernail-sized discs with a biodegradable polycaprolactone backbone that allows the patch to be sutured into place.
As a side benefit nanotubes also make the patches stronger and lower their tendency to swell
This is a good example of how it's much better for an application person like Dr. Jacot to work with experts who know how to handle nanotubes rather than trying to go solo as many do said he.
Biocompatible Carbon nanotube#Chitosan Cardiac Scaffold Matching the Electrical conductivity of the Heart. Seokwon Pok Flavia Vitale Shannon L. Eichmann Omar M. Benavides Matteo Pasquali and Jeffrey G Jacot ACS Nano Just Accepted Manuscript DOI:
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