This flexible new material which the group has identified as a conductive polymer nanocomposite is the latest expression of the ongoing research in Drexel's Department of Materials science and engineering on a family of composite two-dimensional materials called MXENES.
To produce the flexible conductive polymer nanocomposite the researchers intercalated the titanium carbide MXENE with polyvinyl alcohol (PVA)- a polymer widely used as the paper adhesive known as school
This leads to a nanocomposite with a unique combination of properties said Gogotsi. The results of both sets of MXENE testing were published recently in the Proceedings of the National Academy of Sciences.
We have shown that the volumetric capacitance of an MXENE-polymer nanocomposite can be compared much higher to conventional carbon-based electrodes
The testing also revealed hydrophilic properties of the nanocomposite which means that it could have uses in water treatment systems such as membrane for water purification
These characteristics mark the trail heads of a variety of paths for research on this nanocomposite material for applications from flexible armor to aerospace components.
and polymer will affect the properties of the resulting nanocomposite and also exploring other MXENES and stronger and tougher polymers for structural applications.
The structure is called a nanopore: a tiny hole in a ceramic sheet that holds electrolyte to carry the electrical charge between nanotube electrodes at either end.
The existing device is a test but the bitsy battery performs well. First author Chanyuan Liu a graduate student in materials science & engineering says that it can be charged fully in 12 minutes
Many millions of these nanopores can be crammed into one larger battery the size of a postage stamp.
because each nanopore is shaped just like the others which allows them to pack the tiny thin batteries together efficiently.
Coauthor Eleanor Gillette's modeling shows that the unique design of the nanopore battery is responsible for its success. The space inside the holes is so small that the space they take up all added together would be no more than a grain of sand.
#Team grows uniform nanowires A researcher from Missouri University of Science and Technology has developed a new way to grow nanowire arrays with a determined diameter length and uniform consistency.
This approach to growing nanomaterials will improve the efficiency of various devices including solar cells and fuel cells.
These semiconducting nanowires could also replace thin films that cover today's solar panels. Current panels can process only 20 percent of the solar energy they take in.
By applying the nanowires the surface area of the panels would increase and allow more efficient solar energy capture and conversion.
In fuel cells these nanowire arrays can be used to lower production expenses by relying on more cost-efficient catalysts.
or outperform the current use of platinum and show that these nanowire arrays are better catalysts for the oxygen reduction reactions in the cells says Dr. Manashi Nath assistant professor of chemistry at Missouri S&t.
The nanowires which are grown on patterned nanoelectrodes are visible only through an electron microscope. Nath creates the nanowire arrays through a process that she calls confined electrodeposition on lithographically patterned nanoelectrodes.
To grow the nanowires Nath writes an image file that creates a pattern for the shape
and size she wants to produce. Using electron beam lithography she then stamps the pattern onto a polymer matrix
and the nanowires are grown by applying electric current through electrodeposition. Nath grows the nanowires in a parallel pattern
which resembles a series of nails protruding from a piece of lumber. One end is held secure to a metal conductor like copper
To increase the nanowires'surface area Nath can make them hollow in the middle much like carbon nanotubes found in optics and electronics.
The nanowires allow current to travel through them. The polymer which is nonconductive can be removed to allow the wires to stand freely
one-step process for producing these nanopores in a graphene membrane using the photothermal properties of gold nanorods."
which a hot spot on a graphene membrane formed a nanopore with a self-integrated optical antenna.
The hot spot was created by photon-to-heat conversion of a gold nanorod.""We believe our approach opens new avenues for simultaneous electrical and optical nanopore DNA sequencing
and for regulating DNA translocation,"says Zettl, who is also a member of the Kavli Energy Nanoscience Institute (Kavli ENSI).
Nanopore sequencing of DNA, in which DNA strands are threaded through nanoscale pores and read one letter at a time,
Under today's technology, the DNA letters are"read"by an electrical current passing through nanopores fabricated on a silicon chip.
Trying to read electrical signals from DNA passing through thousands of nanopores at once, however, can result in major bottlenecks.
"Direct and enhanced optical signals are obtained at the junction of a nanopore and its optical antenna,"says Lee."
"Simultaneously correlating this optical signal with the electrical signal from conventional nanopore sequencing provides an added dimension that would be an enormous advantage for high-throughput DNA readout."
The dimensions of the nanopores and the optical characteristics of the plasmonic antenna are tunable, with the antenna functioning as both optical signal transducer and enhancer.
so that each base-pair fluoresces at a signature intensity as it passes through the junction of the nanopore and its optical antenna."
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
#Method for symmetry-breaking in feedback-driven self-assembly of optical metamaterials (Phys. org) If you can uniformly break the symmetry of nanorod pairs in a colloidal solution you're a step ahead of the game toward achieving new and exciting metamaterial properties.
This led the group to produce nanostructures that have historically been considered impossible to assemble. The widely used method of metamaterial synthesis is top-down fabrication such as electron beam
Starting with a solution of colloidal nanorods Yang and Ni built on the common self-assembly technique used to build nanoparticles.
The desired product when synthesizing colloidal gold nanorods which are stabilized during growth to obtain preferential bonding along longitudinal facets is pairs of rods
You have a pair of nanorods with no shift at all relative to one another; or a pair that are shifted too much;
This allowed them to separate out the undesired resonances indicating nanorod pairs that are shifted not the desired amount
we use the material's own properties to drive nanostructure formation in solution. This has the intrinsic value of making many structures in one batch.
The unique feedback mechanism leads to precisely controlled nanostructures with beyond conventional symmetries and functionalities.
#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.
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,
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
Using powerful supercomputers researchers at UWA discovered that graphene nanoflakes can significantly enhance the rates of a range of chemical reactions.
and extend the scope of the study to'infinite'graphene sheets rather than graphene nanoflakes he said d
#Researchers patent a nanofluid that improves heat conductivity Researchers at the Universitat Jaume I (UJI) have developed
and patented a nanofluid improving thermal conductivity at temperatures up to 400°C without assuming an increase in costs
The nanofluid developed by the Multiphase Fluids research group at the UJI is the first capable of working at high temperatures (up to 400°C
The cost of this new nanofluid (to which nanoparticles are added in order to enhance and improve heat conductivity) is similar to that of the base fluid,
after testing the thermal properties of the nanofluid and patenting this new technology, the research group has started the phase of searching industrial partners
either to transfer the nanofluid over to them or with whom applications can be researched jointly and developed.
Finally, Juliá notes that the method employed to produce the nanofluid is easily scalable to the industrial level,
the nanofluid developed is based on a heat transfer oil (diphenyl/diphenyl oxide) that is widely used in industry,
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.
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."
and edge configurations scientists have theorized that nanoribbons with zigzag edges are the most magnetic making them suitable for spintronics applications.
This allows the scientists to control the nanoribbons'length edge configuration and location on the substrate.
Paul Weiss distinguished professor of chemistry and biochemistry and a member of UCLA's California Nanosystems Institute developed the method for producing the nanoribbons with Patrick Han and Taro Hitosugi professors at the Advanced Institute
Electronics based on carbon especially carbon nanotubes (CNTS) are emerging as successors to silicon for making semiconductor materials.
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.
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.
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
It is this ability to design arbitrary nanostructures using DNA manipulation that inspired the Wyss team to envision using these DNA structures as practical foundries or molds for inorganic substances.
and testing them on skin we have shown that positively charged nanorod shaped nanoparticles are two to six times more effective at penetrating skin than others says lead author Dr Antonios Kanaras.
in order to create nanostructures and to'draw'substances onto nano-sized regions. The latter is called'nanolithography 'and was used the technique by Professor Evans and his team in this research.
spinning out nanofibers for use in water filters body armor and smart textiles; or propulsion systems for fist-sized nanosatellites.
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
#Creating nanostructures using simple stamps Nanostructures of virtually any possible shape can now be made using a combination of techniques developed by the MESA+Institute for Nanotechnology of the University of Twente.
#Researcher develops optically traceable smart 2-D nanosheet that responds to ph Nanoparticles have the potential to revolutionize the medical industry
the nanosheet. Specifically he designed a strong stable and optically traceable smart 2-D material that responds to ph or the acidity or basicity of its surrounding environment.
Nanosheets are unusual amongst nanotechnology because they do not exactly conform to nanoscale. The sheets that Kim produced are just a few nanometers thick thin enough to earn the nano prefix.
much larger than typical nanostructures.##Nanosheets'structure gives them the ability to change shape from a flat surface to a scroll.
Unfortunately most nanosheets roll and unroll spontaneously. If researchers can design a nanosheet to change form in response to a stimulus they can use it for a number of new applications.
Kim tried adding different polymers to his nanosheets to make them responsive. For this experiment he incorporated a relatively simple polymer that responds to ph. He found that the resulting nanosheet would always curl in basic high ph conditions
and always flatten in acidic low ph conditions. Kim also made his nanosheets responsive to near-infrared light a wavelength of light that is harmless to humans.
Depending on the shape of the nanosheet the near-infrared radiation bounces back with a different wavelength.
In this way Kim can noninvasively track the nanosheets even though he can't see them. Using these optical properties to characterize the nanosheets Kim determined that he could approximate ph. Kim envisions biomedical engineers wrapping drugs inside of scrolled nanosheets
so that when the sheet unrolls it releases the medicine. PH responsive nanosheets for example could prove useful for targeting different parts of the human digestive tract
which changes ph between the acidic stomach and basic intestines. Yet this is only the beginning;
creating a responsive nanosheet is just a matter of adding the right polymer. A nanosheet is like pizza dough Kim said.
Whatever you like to put on it#one topping two toppings anything#you can. A nanosheet with a heat-sensitive polymer could burn surrounding tumors to destroy them functioning as a kind of super-specific chemotherapy.
It's easy to get the nanosheets to the cancer cells explains Kim. Targeting specific tissues is simply a matter of adding the appropriate biomarker
so that the body sends the nanosheet where it belongs. The advantage of the rolling means that this nanosheet can entrap many markers
or drugs securely inside the body said Kim. By encapsulating a dangerous substance such as a cancer-treating drug into a nanosheet doctors can attack very specific parts of the body.
This would decrease the amount of the drug necessary and minimize side effects. There are tons of smart polymers
and metals Kim said explaining the many properties he hopes to incorporate into nanotechnology. This new structure is composite
which means it allows us to mix all different kinds of components. Now Kim just needs to build the right nanosheet for each purpose.
Explore further: Like cling wrap new biomaterial can coat tricky burn wounds and block out infection More information:
Smart Composite Nanosheets with Adaptive Optical Properties Jeong-Hwan Kim Murtaza Bohra Vidyadhar Singh Cathal Cassidy and Mukhles Sowwan Applied materials & Interfaces2014.
American Chemical Society DOI: 10.1021/am504170
#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.
The new technology may significantly enhance the performance. Engineers of LUT have constructed the world's first electrical motor applying a textile material;
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.
The test motor output power is 40 W it rotates at 15000 rpm and has almost a 70%efficiency.
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.
Aydin and his team have created a new nanostructure that absorbs a very narrow spectrum of light#having a bandwidth of just 12 nanometers.
By using nanofabrication techniques in the lab Aydin's team found that removing the insulating layer#leaving only metallic nanostructures#caused the structure to absorb a much narrower band of light.
#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
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.
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:
Briseno with colleagues and graduate students at UMASS Amherst and others at Stanford university and Dresden University of Technology Germany report in the current issue of Nano Letters that by using single-crystalline organic nanopillars
or nanograss they found a way to get around dead ends or discontinuous pathways that pose a serious drawback when using blended systems known as bulk heterojunction donor-acceptor or positive-negative (p-n) junctions for harvesting energy in organic solar cells.
We report here that we have developed at last the ideal architecture composed of organic single-crystal vertical nanopillars.
Nanopillars are engineered nanoscale surfaces with billions of organic posts that resemble blades of grass and like grass blades they are particularly effective at converting light to energy.
In this case the anisotropy is along the nanopillar perpendicular to the substrate. Briseno says The biggest challenge in producing this architecture was finding the appropriate substrate that would enable the molecules to stack vertically.
Vertical nanopillars are ideal geometries for getting around these challenges Briseno says because charge separation/collection is most efficient perpendicular to the plastic device.
In this case our nanopillars highly resemble nanograss. Our systems share similar attributes of grass such as high density array system vertical orientations
We envision that our nanopillar solar cells will appeal to low-end energy applications such as gadgets toys sensors and short lifetime disposable devices s
#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 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
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