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and receive electrons to generate electrical current when exposed to light. The new polymer developed by Yu s group called PID2 improves the efficiency of electrical power generation by 15 percent
when added to a standard polymer-fullerene mixture. ullerene a small carbon molecule is one of the standard materials used in polymer solar cellslu says. asically in polymer solar cells we have a polymer as electron donor
and fullerene as electron acceptor to allow charge separation. n their work the researchers added another polymer into the device resulting in solar cells with two polymers and one fullerene.
In order for a current to be generated by the solar cell electrons must be transferred from polymer to fullerene within the device.
But the difference between electron energy levels for the standard polymer-fullerene is large enough that electron transfer between them is difficult.
which improve the mobility of electrons throughout the material. The fibers serve as a pathway to allow electrons to travel to the electrodes on the sides of the solar cell. t s like you re generating a street
and somebody that s traveling along the street can find a way to go from this end to anotheryu explains.
and convert it into biological fuel their excess electrons flow into the carbon filaments and across to the positive electrode
which is made of silver oxide a material that attracts electrons. The electrons flowing to the positive node gradually reduce the silver oxide to silver storing the spare electrons in the process.
After a day or so the positive electrode has absorbed a full load of electrons and has largely been converted into silver says Xing Xie an interdisciplinary researcher.
At that point it is removed from the battery and re-oxidized back to silver oxide releasing the stored electrons.
Engineers estimate that the microbial battery can extract about 30 percent of the potential energy locked up in wastewater.
which excites electrons that flow through the thylakoid membranes of the chloroplast. The plant captures this electrical energy
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.
and boosted photosynthetic electron flow by about 30 percent. Yet to be discovered is how that extra electron flow influences the plantssugar production. his is a question that we are still trying to answer in the lab:
What is the impact of nanoparticles on the production of chemical fuels like glucose? Giraldo says.
and receives electrons, but can also transfer them into another substance. Hydrogen is virtually everywhere on the planet,
The new material would need enough surface area to move electrons across quickly and evenly and boost the overall electron transfer efficiency.
The researchers also needed a platform on which biological components, like br, could survive and connect with the titanium dioxide catalyst:
which totally changes how the electrons move throughout our system.""Rozhkova's mini-hydrogen generator works like this:
Electrons from this reaction are transmitted to the titanium dioxide on which these two materials are anchored, making the titanium dioxide sensitive to visible light.
and electrons as they converge on the platinum. Examinations using a technique called Electron Paramagnetic Resonance (EPR)
and time-resolved spectroscopy at the Center for Nanoscale Materials verified the movements of the electrons within the system,
while electrochemical studies confirmed the protons were transferred. Tests also revealed a new quirk of graphene behavior."
and accepts electrons, "said Argonne postdoctoral researcher Peng Wang.""Our exploration using EPR allowed us to prove, experimentally,
that graphene also injects electrons into other materials.""Rozhkova's hydrogen generator proves that nanotechnology,
"This research,"Photoinduced Electron Transfer pathways in Hydrogen-Evolving Reduced graphene oxide-Boosted Hybrid Nano-Bio Catalyst,
Using a new operating principle called the hot-electron photothermoelectric effect the research team created a device that is as sensitive as any existing room temperature detector in the terahertz range
because when light is absorbed by the electrons suspended in the honeycomb lattice of the graphene they do not lose their heat to the lattice
Light is absorbed by the electrons in graphene which heat up but don't lose their energy easily.
These heated electrons escape the graphene through electrical leads much like steam escaping a tea kettle.
which conduct electrons at different rates. Because of this conductivity difference more electrons will escape through one than the other producing an electrical signal.
This electrical signal detects the presence of terahertz waves beneath the surface of materials that appear opaque to the human eye or even x-rays.
Graphene has been used among other things to design FETSEVICES that regulate the flow of electrons through a channel via a vertical electric field directed into the channel by a terminal called a gate.
Electrons travel freely across a graphene FETENCE it cannot be switched offhich in this case results in current leakages and higher potential for inaccuracies.
Using the synchrotron Hunt could measure where electrons were on the graphene and how the different oxide groups modified that.
e transferred electrons from the dopant potassium to the surface of the black phosphorus, which confined the electrons
and allowed us to manipulate this state. Potassium produces a strong electrical field which is required what we to tune the size of the band gap. his process of transferring electrons is known as doping
and induced a giant Stark effect, which tuned the band gap allowing the valence and conductive bands to move closer together,
These devices take advantage of the ability of electrons to penetrate barriers, a phenomenon known as quantum tunneling.
The facility world-class equipment includes an instrument known as The swiss Muon Source (S S) which uses muon beams acting as magnetic probes to reveal magnetic properties on a nanoscale.
To take this initial experiment to the next level, the researchers may try to influence the phase transitions by experimenting with the size, shape,
e transferred electrons from the dopant-potassium-to the surface of the black phosphorus, which confined the electrons
and allowed us to manipulate this state. Potassium produces a strong electrical field which is required what we to tune the size of the band gap. his process of transferring electrons is known as doping
and induced a giant Stark effect, which tuned the band gap allowing the valence and conductive bands to move closer together,
#Building the electron superhighway: Vermont scientists invent new approach in quest for organic solar panels and flexible electronics Abstract:
But the basic science of how to get electrons to move quickly and easily in these organic materials remains murky.
what they are calling"an electron superhighway"in one of these materials--a low-cost blue dye called phthalocyanine--that promises to allow electrons to flow faster and farther in organic semiconductors.
"Roughly speaking, an exciton is displaced a electron bound together with the hole it left behind.
the UVM team was able to observe nanoscale defects and boundaries in the crystal grains in the thin films of phthalocyanine--roadblocks in the electron highway."
"We have discovered that we have hills that electrons have to go over and potholes that they need to avoid,
"these stacked molecules--this dish rack--is the electron superhighway.""Though excitons are charged neutrally --and can't be pushed by voltage like the electrons flowing in a light bulb--they can, in a sense, bounce from one of these tightly stacked molecules to the next.
This allows organic thin films to carry energy along this molecular highway with relative ease,
2015flexible Electronics SLAC's ultrafast'electron camera'visualizes ripples in 2-D material: Understanding motions of thin layers may help design solar cells, electronics and catalysts of the future September 10th, 2015realizing carbon nanotube integrated circuits:
2015energy SLAC's ultrafast'electron camera'visualizes ripples in 2-D material: Understanding motions of thin layers may help design solar cells, electronics and catalysts of the future September 10th,
2015solar/Photovoltaic SLAC's ultrafast'electron camera'visualizes ripples in 2-D material: Understanding motions of thin layers may help design solar cells, electronics and catalysts of the future September 10th, 2015hybrid solar cell converts both light and heat from sun's rays into electricity (video) September 9th,
Process uses light-harvesting nanoparticles, captures energy from'hot electrons'September 5th, 201 0
#First realization of an electric circuit with a magnetic insulator using spin waves Abstract: Researchers at the University of Groningen, Utrecht University, the Universit de Bretagne Occidentale and the FOM Foundation have found that it is possible to make an electric circuit with a magnetic insulator.
In our current electronic equipment, information is transported via the motion of electrons. In this scheme, the charge of the electron is used to transmit a signal.
In a magnetic insulator, a spin wave is used instead. Spin is a magnetic property of an electron.
A spin wave is caused by a perturbation of the local magnetisation direction in a magnetic material.
Such a perturbation is caused by an electron with an opposite spin, relative to the magnetisation.
An electron can flow through the platinum, but not in the YIG since it is an insulator.
However, if the electron collides on the interface between YIG and platinum this influences the magnetisation at the YIG surface and the electron spin is transferred.
This causes a local magnetisation direction, generating a spin wave in the YIG. Spin wave detectionthe spin waves that the researchers send into the YIG are detected by the platinum strip on the other side of the YIG.
and transfers its spin to an electron in the platinum. This influences the motion of the electron, resulting in an electric current that the researchers can measure.
The researchers already studied the combination of platinum and YIG in previous research. From this research it was found that
or cooling of the platinum-YIG interface, depending on the relative orientation of the electron spins in the platinum and the magnetisation in the YIG.##
News and information Building the electron superhighway: Vermont scientists invent new approach in quest for organic solar panels and flexible electronics September 14th, 2015pillared graphene gains strength:
Ultrafast terahertz spectroscopy yields direct insight into the building block of modern magnetic memories July 6th, 2015chip Technology Building the electron superhighway:
2015ut researchers give nanosheets local magnetic properties September 11th, 2015discoveries Building the electron superhighway: Vermont scientists invent new approach in quest for organic solar panels and flexible electronics September 14th, 2015pillared graphene gains strength:
When the understanding of complex networks such as the brain or the Internet is applied to geometry the results match up with quantum behavior September 13th, 2015announcements Building the electron superhighway:
Regulations require collaboration to ensure safety September 14th, 2015interviews/Book reviews/Essays/Reports/Podcasts/Journals/White papers Building the electron superhighway:
2015slac's ultrafast'electron camera'visualizes ripples in 2-D material: Understanding motions of thin layers may help design solar cells, electronics and catalysts of the future September 10th, 201 0
The first nanometer resolved image of individual tobacco mosaic virions shows the potential of low energy electron holography for imaging biomolecules at a single particle level--a milestone in structural biology and a potential new tool
The work demonstrates the potential of low energy electron holography as a non-destructive, single-particle imaging technique for structural biology.
Low energy electron holography is a technique of using an electron wave to form holograms. Similar to light optical holography
"The low energy electron holography has two major advantages over conventional microscopy. First, the technique doesn't employ any lenses,
Second, low energy electrons are harmless to biomolecules, "Longchamp said. In many conventional techniques such as transmission electron microscopy, the possible resolution is limited by high-energy electrons'radiation damage to biological samples.
Individual biomolecules are destroyed long before an image of high enough quality can be acquired. In other words, the low permissible electron dose in conventional microscopies is not sufficient to obtain high-resolution images from a single biomolecule.
However in low energy electron holography, the employed electron doses can be much higher--even after exposing fragile molecules like DNA or proteins to a electron dose more than five orders of magnitude higher
than the critical dose in transmission electron microscopy, no radiation damage could be observed. Sufficient electron dose in low energy electron holography makes imaging individual biomolecules at a nanometer resolution possible.
In Longchamp's experiment, the tobacco mosaic virions were deposited on a freestanding, ultraclean graphene, an atomically thin layer of carbon atoms arranged in a honeycomb lattice.
which is conductive, robust and transparent for low energy electrons. To obtain the high-resolution hologram, an atomically sharp, tungsten tip acts as a source of a divergent beam of highly coherent electrons.
When the beam hits the sample, part of the beam is scattered and the other part is affected not.
"Since low energy electron holography is a method very sensitive to mechanical disturbance, the current nanometer resolution could be improved to angstrom (one ten billionth of a meter)
The article"Low energy electron holographic imaging of individual tobacco mosaic virions"is authored by Jean-Nicolas Longchamp, Tatiana Latychevskaia, Conrad Escher and Hans-Werner Fink.
including irradiation with electrons and ions, but none of them worked. So far, the oxygen plasma approach worked the best,
#Researchers create first whispering gallery for graphene electrons (Nanowerk News) An international research group led by scientists at the U s. Commerce departments National Institute of Standards
and Technology (NIST) has developed a technique for creating nanoscale whispering galleries for electrons in graphene. The development opens the way to building devices that focus
and amplify electrons just as lenses focus light and resonators (like the body of a guitar) amplify sound.
issue of Science("Creating and probing electron whispering-gallery modes in graphene")."An international research group led by scientists at NIST has developed a technique for creating nanoscale whispering galleries for electrons in graphene.
The researchers used the voltage from a scanning tunneling microscope (right) to push graphene electrons out of a nanoscale area to create the whispering gallery (represented by the protuberances on the left),
which is like a circular wall of mirrors to the electron. Image: Jon Wyrick, CNST/NIST) In some structures,
such as the dome in St pauls Cathedral in London, a person standing near a curved wall can hear the faintest sound made along any other part of that wall.
These whispering galleries are unlike anything you see in any other electron based system, and thats really exciting.
However, early studies of the behavior of electrons in graphene were hampered by defects in the material.
When moving electrons encounter a potential barrier in conventional semiconductors it takes an increase in energy for the electron to continue flowing.
As a result, they are reflected often, just as one would expect from a ball-like particle.
However, because electrons can sometimes behave like a wave, there is a calculable chance that they will ignore the barrier altogether,
Due to the light-like properties of graphene electrons, they can pass through unimpededno matter how high the barrierif they hit the barrier head on.
This tendency to tunnel makes it hard to steer electrons in graphene. Enter the graphene electron whispering gallery.
To create a whispering gallery in graphene the team first enriched the graphene with electrons from a conductive plate mounted below it.
With the graphene now crackling with electrons, the research team used the voltage from a scanning tunneling microscope (STM) to push some of them out of a nanoscale-sized area.
This created the whispering gallery, which is like a circular wall of mirrors to the electron.
An electron that hits the step head-on can tunnel straight through it, said NIST researcher Nikolai Zhitenev.
But if electrons hit it at an angle, their waves can be reflected and travel along the sides of the curved walls of the barrier until they began to interfere with one another,
creating a nanoscale electronic whispering gallery mode. The team can control the size and strength, i e.,
"We transferred electrons from the dopant-potassium-to the surface of the black phosphorus, which confined the electrons
and allowed us to manipulate this state. Potassium produces a strong electrical field which is required what we to tune the size of the band gap."
"This process of transferring electrons is known as doping and induced a giant Stark effect, which tuned the band gap allowing the valence
The paper states,-rays radiated by relativistic electrons driven by well-controlled high-power lasers offer a promising route to a proliferation of this powerful imaging technology.
and wiggles electrons, giving rise to a brilliant kev X-ray emission. his so-called betatron radiation is emitted in a collimated beam with excellent spatial coherence and remarkable spectral stability.
The X-rays required were generated by electrons that were accelerated to nearly the speed of light over a distance of approximately one centimeter by laser pulses lasting around 25fs.
and their electrons like a ship through water, producing a wake of oscillating electrons. This electron wave creates a trailing wave-shaped electric field structure on which the electrons surf and by
which they are accelerated in the process. The particles then start to vibrate, emitting X-rays. Each light pulse generates an X-ray pulse.
"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."
"When sunlight is absorbed, photo-excited electron? hole pairs are generated in the silicon and titanium oxide nanowires,
The photo-generated electrons in the silicon will be passed onto bacteria for the CO2 reduction while the photo-generated holes in the titanium oxide split water molecules to make oxygen."
For this study, the Berkeley team used Sporomusa ovata, an anaerobic bacterium that readily accepts electrons directly from the surrounding environment
"Decorating monolayer graphene with a layer of lithium atoms enhances the graphene's electron-phonon coupling to the point where superconductivity can be induced,
"Decorating monolayer graphene with a layer of lithium atoms enhances the graphene's electron-phonon coupling to the point where superconductivity can be stabilized."
"Decorating monolayer graphene with a layer of lithium atoms enhances the graphene's electron-phonon coupling to the point where superconductivity can be induced,
"Decorating monolayer graphene with a layer of lithium atoms enhances the graphene's electron-phonon coupling to the point where superconductivity can be stabilized."
supplies beams from exotic elementary particles called muons, which can be used to study nanomagnetic properties. The project took place in collaboration with a research group headed by Stephen Lee from the University of St andrews, Scotland n
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.
photo-excited electron#hole pairs are generated in the silicon and titanium oxide nanowires, which absorb different regions of the solar spectrum.
The photo-generated electrons in the silicon will be passed onto bacteria for the CO2 reduction while the photo-generated holes in the titanium oxide split water molecules to make oxygen.
the Berkeley team used Sporomusa ovata, an anaerobic bacterium that readily accepts electrons directly from the surrounding environment
Mass-Selected Photoelectron Circular Dichroism (MS-PECD) uses circularly polarised light produced by a laser to ionise the molecules using a couple of photons to knock an electron out of the chiral molecule to leave a positively charged ion behind.
By tracking the direction that the electrons take when they travel out of the molecule
which a small electrical potential is applied to the negatively charged electron and positively charged ion which draws them out in opposite directions.
and electron those reaching the detectors simultaneously are very likely to have come from the same molecule.
and matched with its partner electron. By combining these methods, it is possible to identify both the handedness of individual molecules and the proportion of left-and right-handed molecules in a mixture.
The research, Enantiomer Specific Analysis of Multi-Component Mixtures by Correlated Electron Imaging-Ion Mass Spectrometry
In this process, electrons are released as a waste product. By providing an electrode for the microorganisms to donate their electrons to
the electrons can be harvested as electricity. Research has shown that plant-growth isn compromised by harvesting electricity,
so plants keep on growing while electricity is produced concurrently. Just imagine, a house with a roof full of plant/tree life powering your home.
In graphene, infrared light launches ripples through the electrons at the surface of this metallike material called surface plasmon polaritons that the researchers were able to control using a simple electrical circuit.
carrying electrons with almost no resistance even at room temperature, a property known as ballistic transport. Graphene's unique optical, mechanical and electrical properties have lead to the one-atom-thick form of carbon being heralded as the next generation material for faster, smaller, cheaper and less power-hungry electronics."
#Hematite're-growth'smoothes rough edges for clean energy harvest (Nanowerk News) Finding an efficient solar water splitting method to mine electron-rich hydrogen for clean
Tunneling electrons from a scanning tunneling microscope tip excites phonons in graphene. The image shows the graphene lattice with blue arrows indicating the motion direction of that carbon atoms for one of the low energy phonon modes in graphene.
issue of Physical Review Letters("Strong Asymmetric Charge Carrier Dependence in Inelastic Electron Tunneling Spectroscopy of Graphene Phonons").
One way to measure these tiny vibrations is to bounce electrons off the material and measure how much energy the electrons have transferred to the vibrating atoms.
But it's difficult. The technique, called inelastic electron tunneling spectroscopy, elicits only a small blip that can be hard to pick out over more raucous disturbances."
"Researchers are faced frequently with finding ways to measure smaller and smaller signals, "says NIST researcher Fabian Natterer,
such as that supplied by the electrons in a scanning tunneling microscope (STM). To filter the phonons'signal from other distractions,
NIST researchers used their STM to systematically alter the number of electrons moving through their graphene device.
As the number of electrons were varied, the unwanted signals also varied in energy, but the phonons remained fixed at their characteristic frequency.
Averaging the signals over the different electron concentrations diluted the annoying disturbances, but reinforced the phonon signals.
which become filled with electrons and stop the phonons from vibrating when we switch from hole to electron doping."
"The team notes that this effect is similar to resonance-induced effects seen in small molecules.
The movement of electrons caused by friction was able to generate enough energy to power the lights
carrying electrons with almost no resistance even at room temperature, a property known as ballistic transport. Graphene's unique optical, mechanical and electrical properties have lead to the one-atom-thick form of carbon being heralded as the next generation material for faster, smaller, cheaper and less power-hungry electronics."
the color of fluorescence shifts into the highly desirable, blue spectral range and the capacity to transport electrons is improved substantially.
"As they eat, the bacteria produce electrons and protons. The voltage that arises between these particles generates energy that we can exploit.
but which could also transfer electrons to a metal electrode, "he says. The idea behind this water purification approach was born many years ago
Silicene great promise is related to how electrons can streak across it at incredible speed close to the speed of light.
Propelling the electrons in silicene requires minimal energy input, which means reducing power and cooling requirements for electronic devices. f silicene could be used to build electronic devices,
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