#Thermal properties of nanowires-Follow the heat A mathematical model of heat flow through miniature wires could help develop thermoelectric devices that efficiently convert heat even their own waste heat into electricity.
Phonons typically move in straight lines in nanowires threads barely a few atoms wide. Previous calculations suggested that if parts of a nanowire contained random arrangements of two different types of atoms,
phonons would be stopped in their tracks. In actual alloy nanowires though, atoms of the same element might cluster together to form short sections composed of the same elements.
Now, Zhun-Yong Ong and Gang Zhang of the A*STAR Institute Of high Performance Computing in Singapore have calculated the effects of such short-range order on the behavior of phonons("Enhancement and reduction of one-dimensional
"Their results suggest that heat conduction in a nanowire does not just depend on the relative concentrations of the alloy atoms and the difference in their masses;
Their model simulated an 88-micrometer-long nanowire containing 160,000 atoms of two different elements.
when the nanowire was ordered more containing clusters of the same elements low-frequency phonons struggled to Move in contrast,
The researchers used their model to study the thermal resistance of a nanowire containing an equal mix of silicon and germanium atoms.
-and high-frequency phonons to heat conduction could also help researchers tune the thermal properties of nanowires in the laboratory.
For instance, the surface roughening of nanowires is known to reduce the thermal conductivity contribution of high-frequency phonons
Black silicon consists of clusters of microscopic vertical pillars, or nanowires. Incoming light bouncing between individual silicon nanowires cannot escape the complex structure,
"Silicon nanowire towers make up dark regions of the flexible Fresnel zone lenses. Each individual lens resembles a bull-eye of alternating light and dark.
Black silicon consists of clusters of microscopic vertical pillars, or nanowires. Incoming light bouncing between individual silicon nanowires cannot escape the complex structure,
Scientists with the U s. Department of energy (DOE)' s Lawrence Berkeley National Laboratory (Berkeley Lab) and the University of California (UC) Berkeley have created a hybrid system of semiconducting nanowires and bacteria
The paper is titled"Nanowire-bacteria hybrids for unassisted solar carbon dioxide fixation to value-added chemicals.""The other corresponding authors and leaders of this research are chemists Christopher Chang and Michelle Chang.
"In our system, nanowires harvest solar energy and deliver electrons to bacteria, where carbon dioxide is reduced and combined with water for the synthesis of a variety of targeted, value-added chemical products."
"By combining biocompatible light-capturing nanowire arrays with select bacterial populations, the new artificial photosynthesis system offers a win/win situation for the environment:
the morphology of the nanowire array protects the bacteria like Easter eggs buried in tall grass
"The system starts with an"artificial forest"of nanowire heterostructures, consisting of silicon and titanium oxide nanowires, developed earlier by Yang and his research group."
"Our artificial forest is similar to the chloroplasts in green plants, "Yang says.""When sunlight is absorbed, photo-excited electron?
hole pairs are generated in the silicon and titanium oxide nanowires, which absorb different regions of the solar spectrum.
"Once the forest of nanowire arrays is established, it is populated with microbial populations that produce enzymes known to selectively catalyze the reduction of carbon dioxide.
"We were able to uniformly populate our nanowire array with S. ovata using buffered brackish water with trace vitamins as the only organic component."
and catalytic activity that is made possible by the nanowire/bacteria hybrid technology. With this approach
and it possesses two nanowires that can be used as contacts. The diarylethene is an insulator
The diarylethene needs to be attached at the end of the nanowires to electrodes so that the current can flow."
using a combination of semiconducting nanowires and bacteria. The research, detailed in the online edition of Proceedings of the National Academy of Sciences in August, builds on a similar hybrid system, also recently devised by Yang and his colleagues,
the primary component of natural gas, using a combination of semiconducting nanowires and bacteria. The research, detailed in the online edition of Proceedings of the National Academy of Sciences in August, builds on a similar hybrid system, also recently devised by Yang and his colleagues,
The detectors rely on superconducting nanowires made of molybdenum silicide. They can record more than 80 percent of arriving photons,
Scientists with the U s. Department of energy (DOE) Lawrence Berkeley National Laboratory (Berkeley Lab) and the University of California (UC) Berkeley have created a hybrid system of semiconducting nanowires and bacteria that mimics
nanowires harvest solar energy and deliver electrons to bacteria, where carbon dioxide is reduced and combined with water for the synthesis of a variety of targeted, value-added chemical products.
By combining biocompatible light-capturing nanowire arrays with select bacterial populations, the new artificial photosynthesis system offers a win/win situation for the environment:
the morphology of the nanowire array protects the bacteria like Easter eggs buried in tall grass
The system starts with an rtificial forestof nanowire heterostructures, consisting of silicon and titanium oxide nanowires,
developed earlier by Yang and his research group. ur artificial forest is similar to the chloroplasts in green plants,
photo-excited electron#hole pairs are generated in the silicon and titanium oxide nanowires, which absorb different regions of the solar spectrum.
Once the forest of nanowire arrays is established, it is populated with microbial populations that produce enzymes known to selectively catalyze the reduction of carbon dioxide.
says Michelle Chang. e were able to uniformly populate our nanowire array with S. ovata using buffered brackish water with trace vitamins as the only organic component.
and catalytic activity that is made possible by the nanowire/bacteria hybrid technology. With this approach, the Berkeley team achieved a solar energy conversion efficiency of up to 0. 38-percent for about 200 hours under simulated sunlight,
or nanowires. Incoming light bouncing between individual silicon nanowires cannot escape the complex structure, making the material darker than dark.
#Niobium Nanowire Yarns Make High-performance Supercapacitors Using yarns made from niobium nanowire, researchers at MIT have developed a new approach to making supercapacitors.
The new approach uses yarns, made from nanowires of the element niobium, as the electrodes in tiny supercapacitors (which are essentially pairs of electrically conducting fibers with an insulator between).
and that niobium nanowire yarn is a promising alternative. magine youe got some kind of wearable health-monitoring system,
The new nanowire-based supercapacitor exceeds the performance of existing batteries, while occupying a very small volume. f youe got an Apple Watch and
500 degrees Celsius so devices made from these nanowires could potentially be suitable for use in high-temperature applications.
individual niobium nanowires are just 140 nanometers in diameter 140 billionths of a meter across,
#Nanowires Boost Hydrogen Production from Sunlight Tenfold Using the energy of the sun to split water into hydrogen
when illuminated by sunlightade from an array of gallium phosphide nanowires. Previously, researchers used flat surfaces of the semiconductor gallium phosphide as the photocathode,
The Gap nanowires, about 500 nm long and 90 nm thick, increased enormously the surface of the photocathode exposed to light.
At the same time, the nanowires allowed a drastic reduction in the use of Gap material . or the nanowires we needed ten thousand times less precious Gap material than in cells with a flat surface.
That makes these kinds of cells potentially a great deal cheaper said Erik Bakkers of Eindhoven University of Technology,
researchers lay out a mesh of nanowires sandwiched in layers of organic polymer. The first layer is dissolved then, leaving the flexible mesh,
#Gallium Phosphide Nanowires Significantly Increase Efficiency of Solar fuel Cells The solar cell made of gallium phosphide (Gap) generates clean fuel hydrogen gas from Water gap is a compound containing phosphide and gallium which also acts
If the gallium phosphide is processed in the form of tiny nanowires, the efficiency of the solar cell can be increased tenfold without using considerable amounts of costly material.
The team resolved this issue by fabricating a network of small Gap nanowires which measured 90nm in width and 500nm in length.
or the nanowires we needed ten thousand less precious Gap material than in cells with a flat surface.
Nanowire...Forget the Insane Mode: Elon musk says Tesla's new...'We're changing the conversation from top speeds,
Thomas Sand Jespersen an associate professor at the University of Copenhagen who helped create the material says it's a way to make a perfect transition between the nanowire and a superconductor.
Nanowires are extremely thin nanocrystal threads used in the development of new electronic components like transistors and solar cells.
Part of the challenge of working with nanowires is creating a good transition between these nanowires and an electrical contact to the outside world.
Up until now researchers have cultured nanowires and the contact separately. However with the new approach both the quality and the reproducibility of the contact have improved considerably.
The atoms sit in a perfectly ordered lattice in the nanowire crystal not only in the semiconductor and the metal but also in the transition between the two very different components which is significant in itself explains Peter Krogstrup an assistant professor who helped develop the contact.
Krogstrup says it is the ultimate limit to how perfect a transition one could imagine between a nanowire crystal and a contact.
and its properties and has shown also that they can make a chip with billions of identical semiconductor-metal nanowire hybrids.
#Electromagnetic field Activated Drug Loadded Nanowires Drug releasing implants can be of great benefit for conditions requiring long term treatment in a targeted area of the body.
Researchers at Purdue University have come up with a new way of releasing drugs into the body in a controlled manner using tiny injectable nanowire implants.
"they stretched defect-free palladium nanowires, each a thousand times thinner than a human hair, under tightly controlled conditions.
This thermal uncertainty in the failure limit suggests that the point where a failure-inducing defect first appears is on the nanowire surface,
which cuts across the nanowire, causing it to break. The study was led by graduate student Lisa Chen and associate professor Daniel Gianola of the Department of Materials science and engineering in Penn School of engineering and Applied science.
The researchers grew palladium nanowires through a vapor deposition method at high temperature, which provided each atom with the time
Welding a nanowire to a grip attached to a series of slanted bars that expand
the researchers could then stretch the nanowire in a controlled way. By repeatedly ramping up the voltage to a different maximum and bringing it down at the same rate,
Gianola said. ur goal was to deduce the point where the first of the nanowire atoms begin to shift out of their original positions
Absent defect-free nanowires to run physical experiments upon, earlier theories and analyses suggested that the relationship between temperature
knowing the temperature would allow one to estimate a nanowire failure limit. By conducting their stretching experiments at various temperatures,
but you have to take a different approach to specify the strength of the nanowire.
t been very difficult to make defect-free nanowires. But now that we can, there a reason to care about how they fail.
and#30 m in length (a human hair ranges from 17 to 181 m). The nanowires were mixed into a liquid elastic material
Ning group started pursuing the distinctive properties of nanomaterials, such as nanowires or nanosheets, more than 10 years ago.
Six years ago, under U s army Research Office funding, they demonstrated that one could indeed grow nanowire materials in a wide range of energy bandgaps
Later on they realized simultaneous laser operation in green and red from a single semiconductor nanosheet or nanowires.
2015ultra-thin nanowires can trap electron'twisters'that disrupt superconductors February 24th, 2015simulating superconducting materials with ultracold atoms:
2015experiment and theory unite at last in debate over microbial nanowires: New model and experiments settle debate over metallic-like conductivity of microbial nanowires in bacterium March 4th,
2015magnetic vortices in nanodisks reveal information: Researchers from Dresden and Jlich use microwaves to read out information from smallest storage devices March 4th, 2015nanosorbents Increase Extraction, Recycling of Silver from Aqueous solutions March 4th, 201 1
2015new nanowire structure absorbs light efficiently: Dual-type nanowire arrays can be used in applications such as LEDS and solar cells February 25th, 2015qd Vision Named Edison Award Finalist for Innovative Color IQ Quantum dot Technology
February 23rd, 2015flexible Electronics Breakthrough in OLED technology March 2nd, 2015discoveries 30 years after C60: Fullerene chemistry with silicon:
Image-dipole distortionsjqi fellow Edo Waks and his colleagues have performed nanoscopic mappings of the electromagnetic field profile around silver nanowires by positioning quantum dots (the emitter) nearby.
Previous work summarized at http://jqi. umd. edu/news/using-single-quantum dots-probe-nanowires. They discovered that sub-wavelength imaging suffered from a fundamental problem,
namely that an"image dipole"induced in the surface of the nanowire was distorting knowledge of the quantum dot's true position.
(as if the nanowire were acting as a sort of funhouse mirror). The JQI experiment successfully measured the image-dipole effect
The resulting work provides a more accurate map of the electromagnetic fields surrounding the nanowire. The JQI scientists published their results in the journal Nature Communications.
2015new nanowire structure absorbs light efficiently: Dual-type nanowire arrays can be used in applications such as LEDS and solar cells February 25th,
2015ultra-thin nanowires can trap electron'twisters'that disrupt superconductors February 24th, 2015discoveries Quantum computing: 1 step closer with defect-free logic gate-Developing a new approach to quantum computing, based on braided quasiparticles as a logic gate to speed up computing,
first requires understanding the potential error-inducing factors March 19th, 2015click! That's how modern chemistry bonds nanoparticles to a substrate March 19th, 2015new optical materials break digital connectivity barriers:
2015new nanowire structure absorbs light efficiently: Dual-type nanowire arrays can be used in applications such as LEDS and solar cells February 25th, 2015qd Vision Named Edison Award Finalist for Innovative Color IQ Quantum dot Technology February 23rd,
2015sensors The Universitat Politcnica de Valncia is coordinating a European project to develop a device for the quick and early diagnosis of cancer March 7th,
2015experiment and theory unite at last in debate over microbial nanowires: New model and experiments settle debate over metallic-like conductivity of microbial nanowires in bacterium March 4th,
2015pens filled with high-tech inks for do-it-yourself sensors March 3rd, 2015researchers build atomically thin gas and chemical sensors:
the researchers grew arrays of iron-nickel nanowires inside the pores of anodized alumina oxide templates,
then dissolved the templates to obtain the bare hybrid nanowires. After that, the researchers exposed the nanowires in an oxygen environment at high temperature (450 degrees Celsius) for a short time,
eventually developing a highly porous iron oxide-nickel oxide hybrid shell around the iron-nickel core."
"Laser-assembled nanowires For the first step in grid construction, the team took advantage of their recent invention of laser zone annealing (LZA) to produce the extremely localized thermal spikes needed to drive ultra-fast self-assembly.
and transforms them into functional nanowires. Layer-by-layer lattice The first completed nanowire array acts as the foundation of the full lattice.
Additional layers each one following variations on that same process, are stacked then to produce customized, crisscrossing configurations--like chain-link fences 10,000 times thinner than a human hair."
"The direction of the laser sweeping across each unassembled layer determines the orientation of the nanowire rows,
"For example, a single layer of platinum nanowires conducts electricity in only one direction, but a two-layer mesh conducts uniformly in all directions."
#Nanowire implants offer remote-controlled drug delivery Abstract: Remote-controlled Eradication of Astrogliosis in Spinal cord Injury via Electromagnetically-induced Dexamethasone Release from"Smart"Nanowireswen Gao and Richard Borgenswe describe a system to deliver drugs to selected tissues continuously,
novel vertically aligned electromagnetically-sensitive Polypyrrole Nanowires (Ppynws). Approximately 1-2mm 2 Dexamethasone (DEX) doped Ppynws was lifted on a single drop of sterile water by surface tension,
A team of researchers has created a new implantable drug-delivery system using nanowires that can be controlled wirelessly.
The nanowires respond to an electromagnetic field generated by a separate device, which can be used to control the release of a preloaded drug.
The nanowires are made of polypyrrole, a conductive polymer material that responds to electromagnetic fields. Wen Gao, a postdoctoral researcher in the Center for Paralysis Research who worked on the project with Borgens
grew the nanowires vertically over a thin gold base, like tiny fibers making up a piece of shag carpet hundreds of times smaller than a human cell.
The nanowires can be loaded with a drug and, when the correct electromagnetic field is applied, the nanowires release small amounts of the payload.
This process can be started and stopped at will, like flipping a switch, by using the corresponding electromagnetic field stimulating device,
and transported a patch of the nanowire carpet on water droplets that were used used to deliver it to the site of injury.
The nanowire patches adhere to the site of injury through surface tension Gao said. The magnitude and wave form of the electromagnetic field must be tuned to obtain the optimum release of the drug,
Functional Drug Delivery Using Electromagnetic field-Responsive Polypyrrole Nanowires, "was published in the journal Langmuir. Other team members involved in the research include John Cirillo,
A 1-2 millimeter patch of the nanowires doped with dexamethasone was placed onto spinal cord lesions that had been exposed surgically,
and those that received a nanowire patch but were exposed not to the electromagnetic field. In some cases, treated mice had no detectable GFAP signal.
2015irt Nanoelec Partners Achieve 3d Chip-stacking Technology & 3d Network-on-chip Framework for Digital Processing July 9th, 2015ultra-thin, all-inorganic molecular nanowires successfully compounded July 8th,
2015ultra-thin, all-inorganic molecular nanowires successfully compounded July 8th, 2015surfing a wake of light: Researchers observe and control light wakes for the first time July 6th,
Layered semiconducting black arsenic phosphorus as an alternative to silicon July 9th, 2015ultra-thin, all-inorganic molecular nanowires successfully compounded July 8th, 2015down to the quantum dot:
#Researchers find nanowires have pronounced unusually'anelastic'properties Anelastic materials exhibit gradual full recovery of deformation once a load is removed, leading to efficient dissipation of internal mechanical energy.
and p-doped Si nanowires (NWS) can exhibit anelastic behaviour that is up to four orders of magnitude larger than the largest anelasticity observed in bulk materials, with a recovery time-scale in the order
Researchers from North carolina State university and Brown University have found that nanoscale wires (nanowires) made of common semiconductor materials have pronounced a anelasticity-meaning that the wires,
"Because nanowires are so small, the anelasticity is significant and easily observed --although it was a total surprise
when we first discovered the anelasticity in nanowires.""The anelasticity was discovered when Zhu and his students were studying the buckling behavior of nanowires."
"Anelasticity is a fundamental mechanical property of nanowires, and we need to understand these sort of mechanical behaviors
if we want to incorporate nanowires into electronics or other devices,"says Elizabeth Dickey, a professor of materials science and engineering at NC State and co-author of the paper.
Nanowires hold promise for use in a variety of applications, including flexible, stretchable and wearable electronic devices.
The researchers worked with both zinc oxide and silicon nanowires, and found that -when bent-the nanowires would return more than 80 percent of the way to their original shape instantaneously,
but return the rest of the way (up to 20 percent) slowly.""In nanowires that are approximately 50 nanometers in diameter,
it can take 20 or 30 minutes for them to recover that last 20 percent of their original shape,
The work was done using tools developed in Zhu's group that enabled the team to conduct experiments on nanowires
If you think of the bent nanowire as an arch, the atoms are moving from the inside of the arch to the outside.
"This phenomenon is pronounced in nanowires. For instance, zinc oxide nanowires exhibited anelastic behavior that is up to four orders of magnitude larger than the largest anelasticity observed in bulk materials,
with a recovery time-scale in the order of minutes,"says Huajian Gao, a professor at Brown University and co-corresponding author of the paper.
Detailed modeling by Gao's group indicates that the pronounced anelasticity in nanowires is because it is much easier for atoms to move through nanoscale materials than through bulk materials.
nanowires can be bent much further than thicker wires without becoming permanently deformed or breaking.""A reviewer commented that this is a new important page in the book on mechanics of nanostructures,
#Nanowires give'solar fuel cell'efficiency a tenfold boost: Eindhoven researchers make important step towards a solar cell that generates hydrogen A solar cell that produces fuel rather than electricity.
Processing the gallium phosphide in the form of very small nanowires is novel and helps to boost the yield by a factor of ten.
The researchers have overcome this problem by making a grid of very small Gap nanowires, measuring five hundred nanometers (a millionth of a millimeter) long and ninety nanometers thick.
"For the nanowires we needed ten thousand less precious Gap material than in cells with a flat surface.
nanostructures (such as nanowires) must be paced into dense"nanostructure forests, "producing 3-D nanogeometries in which ions and electrons must rapidly move.
researchers lay out a mesh of nanowires sandwiched in layers of organic polymer. The first layer is dissolved then, leaving the flexible mesh,
"Laser-assembled nanowires For the first step in grid construction, the team took advantage of their recent invention of laser zone annealing (LZA) to produce the extremely localized thermal spikes needed to drive ultra-fast self-assembly.
and transforms them into functional nanowires. Layer-by-layer lattice The first completed nanowire array acts as the foundation of the full lattice.
Additional layers each one following variations on that same process, are stacked then to produce customized, crisscrossing configurationsike chain-link fences 10,000 times thinner than a human hair."
"The direction of the laser sweeping across each unassembled layer determines the orientation of the nanowire rows,
"For example, a single layer of platinum nanowires conducts electricity in only one direction, but a two-layer mesh conducts uniformly in all directions."
and selectively filled via epitaxy to create arbitrary shaped III-V semiconductors such as nanowires, cross junctions, nanostructures containing constrictions and 3d stacked nanowires.
Using this small seed area epitaxy, today at the VLSI Symposium in Kyoto, IBM scientist Lukas Czornomaz is presenting a solution for large scale and controlled integration of high quality Ingaas on bulk Silcon (Si)
#Novel method creates nanowires with new useful properties (Nanowerk News) Harvard scientists have developed a first-of-its-kind method of creating a class of nanowires that one day could have applications in areas ranging from consumer electronics to solar panels.
but researchers for years have recognized a similar phenomenon in nanowires. When heated to extreme temperatures
Day and Mankin heated traditionally grown nanowires to just below that transformation point in a vacuum chamber,
when nanowires break down at high temperatures. Unlike with the droplets, though, the process can be controlled tightly.
Along with duplicating the process in nanowires between 20 and 100 nanometers in diameter, researchers demonstrated the process using several combinations of materials,
In addition to being able to tune the distance between the lobes on nanowires, Mankin said tests showed they were also able to tune the cross-section of the wires.
What that means is that you could absorb the same amount of infrared light with these nanowires as you could with traditional silicon materials that are 100 times thicker.
if you wanted to use nanowires for photo-detection of green and blue light, youd need two wires,
researchers lay out a mesh of nanowires sandwiched in layers of organic polymer. The first layer is dissolved then, leaving the flexible mesh,
the secret to these new prototype solar cells are gallium phosphide nanowires, which can split water into its hydrogen
So the researchers tried producing a grid of tiny gallium phosphide nanowires measuring 90 nanometres thick and 500 nanometers long,
"For the nanowires we needed 10,000 less precious Gap material than in cells with a flat surface.
#New superconducting hybrid crystals A new type of'nanowire'crystals that fuses semiconducting and metallic materials on the atomic scale could lay the foundation for future semiconducting electronics.
"Our new material was born as a hybrid between a semiconducting nanowire and its electronic contact.
Thus we have invented a way to make a perfect transition between the nanowire and a superconductor.
ever since research into nanowire crystals has existed at the Nanoscience Center at the Niels Bohr Institute.
Nanowire and contact formed at the same time Nanowires are extremely thin nanocrystal threads used in the development of new electronic components
Part of the challenge of working with nanowires is creating a good transition between these nanowires and an electrical contact to the outside world.
but from all over the world, have cultured nanowires and the contact separately. However, with the new approach, both the quality and the reproducibility of the contact have improved considerably."
"The atoms sit in a perfectly ordered lattice in the nanowire crystal, not only in the semiconductor and the metal,
You could say that it is the ultimate limit to how perfect a transition one could imagine between a nanowire crystal and a contact.
Chips with billions of nanowire hybrids In their publication in Nature Materials, the research group has demonstrated this perfect contact
and its properties and has shown also that they can make a chip with billions of identical semiconductor-metal nanowire hybrids."
and that is why the research into nanowires is interesting for the largest electronics companies, "says Thomas Sand Jespersen.
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