For example, the turbine blades in electric power plants become less efficient if water builds up on their surfaces. f you can make the blades stay dry longer,
When an earthquake and tsunami struck Japan Fukushima nuclear power plant in 2011, knocking out emergency power supplies,
crews sprayed seawater on the reactors to cool them to no avail. One possible reason:
and nuclear engineering at Rensselaer Polytechnic institute who was involved not in this research, says, xtending the surface temperature at which this phenomenon occurs is a challenging task that has been a century-long research effort.
even at the extremely low power levels characteristic of tiny solar cells. Previous ultralow-power converters that used the same approach had efficiencies of only 40 or 50 percent.
Where most of its ultralow-power predecessors could use a solar cell to either charge a battery
Ups and downs The circuit chief function is to regulate the voltages between the solar cell, the battery,
and falls depends on the voltage generated by the solar cell, which is highly variable. So the timing of the switch throws has to vary, too.
whose selection is determined by the solar cell voltage. Once again, when the capacitor fills, the switches in the inductor path are flipped. n this technology space,
and release electrical power in such bursts, which are needed for brief transmissions of data from wearable devices such as heart-rate monitors, computers,
and water to promote the desired reactions critical guidance for the design of commercial-scale reactors.
In both cases, they removed samples from their reactor vessel at regular intervals up to 30 minutes.
Knowing what those conditions are inside a practical reactor is a parallel challenge. When oil is injected into flowing SCW,
Power electronics is a ubiquitous technology used to convert electricity to higher or lower voltages and different currents such as in a laptop power adapter
or in electric substations that convert voltages and distribute electricity to consumers. Many of these power-electronics systems rely on silicon transistors that switch on
Currently, these data centers eat up about 2 percent of electricity in the United states. But Gan-based power electronics
#New technique helps probe performance of organic solar cell materials A research team led by North carolina State university has developed a new technique for determining the role that a material's structure has on the efficiency of organic solar cells
There have been a lot of studies looking at the efficiency of organic solar cells but the energy conversion process involves multiple steps
Broadly speaking organic solar cells convert light into electric current in four steps. First the cell absorbs sunlight which excites electrons in the active layer of the cell.
In previous organic solar cell research there was ambiguity about whether differences in efficiency were due to dissociation or charge collection#because there was no clear method for distinguishing between the two.
so that it runs parallel to the long axis of organic solar cell molecules it will be absorbed; but if the light runs perpendicular to the molecules it passes right through it.
The researchers created highly organized nanostructures within a portion of the active layer of an organic solar cell meaning that the molecules in that portion all ran the same way.
or just the disorganized section#even though they were on the same active layer of the same solar cell.
and nanostructure features are needed to advance organic solar cell technology. Explore further: Hybrid materials could smash the solar efficiency ceiling More information:
Awartani O. Kudenov M. W. Kline R. J. and O'connor B. T. 2015) In-Plane Alignment in Organic solar cells to Probe the Morphological Dependence of Charge Recombination.
The collaborating group from Rensselaer Polytechnic institute is led by Diana Borca-Tasciuc, associate professor of mechanical, aerospace and nuclear engineering.
#Researchers create novel nanobowl optical concentrator for organic solar cell Geometrical light trapping is a simple and promising strategy to largely improve the optical absorption and efficiency of solar cells.
Meanwhile light trapping by nano-textured substrate is an appealing strategy to improve solar cell efficiency.
The novel nanobowl optical concentrator developed by Professor Zhiyong Fan can largely enhance the optical absorption in the active layer of organic solar cell
In addition they have investigated the effect of geometry of nanobowl on the solar cell performance and three types of nanobowl with pitch of 1000 nm 1200 nm and 1500 nm were studied.
Solar cells based on nanobowl with pitch of 1000 nm exhibited the best photon absorption in photoactive layer leading to the highest short-circuit current density of 9. 41 ma cm-2 among all nanobowl substrates.
With open-circuit voltage of 0. 573 V and fill factor of 57.9%this nanobowl solar cell achieved a solar energy conversion efficiency of 3. 12
#Carbon nanoballs can greatly contribute to sustainable energy supply Researchers at Chalmers University of Technology have discovered that the insulation plastic used in high-voltage cables can withstand a 26 per cent higher voltage
which are needed to achieve a sustainable energy system. The renewable energy sources of tomorrow will often be found far away from the end user.
"Reducing energy losses during electric power transmission is one of the most important factors for the energy systems of the future,
Carbon nanoballs can greatly contribute to sustainable energy supply An electrical tree, which is a major electrical breakdown mechanism of insulation plastic.
Carbon nanoballs can greatly contribute to sustainable energy supply Wind turbines are most effective when placed out at sea.
the researchers tested a number of molecules that are used also within organic solar cell research at Chalmers.
whether the crystalline structure of the materials is mismatched-lowering the manufacturing cost for a wide variety of semiconductor devices such as solar cells lasers and LEDS.
For example in photonic devices like solar cells lasers and LEDS the junction is where photons are converted into electrons or vice versa.
This manufacturing cost is a major reason why semiconductor devices such as solar cells lasers and LEDS remain very expensive.
and harvest hydrogen is one of the most intriguing ways to achieve clean energy. Automakers have started introducing hydrogen fuel cell vehicles
But making hydrogen which mostly comes from natural gas requires electricity from conventional carbon dioxide-emitting power plants.
Producing hydrogen at low cost from water using the clean energy from the sun would make this form of energy
not much material is needed for microsensors, miniature through-flow reactors, or other potential applications. Ensinger's team has tested already successfully one use of the gold nanotubes:
The gold nanotubes conduct electricity especially well due to their one-dimensional structure. In addition, they are relatively long
#Lengthening the life of high capacity silicon electrodes in rechargeable lithium batteries A new study will help researchers create longer-lasting higher-capacity lithium rechargeable batteries
In a study published in the journal ACS Nano researchers showed how a coating that makes high capacity silicon electrodes more durable could lead to a replacement for lower-capacity graphite electrodes.
Understanding how the coating works gives us an indication of the direction we need to move in to overcome the problems with silicon electrodes said materials scientist Chongmin Wang of the Department of energy's Pacific Northwest National Laboratory.
Silicon electrodes aren't very durable#after a few dozen recharges they can no longer hold electricity. That's partly due to how silicon takes up lithium#like a sponge.
and thoroughly#an improvement over earlier silicon electrodes#but only partly alleviates the fracturing problem. Last year materials scientist Chunmei Ban and her colleagues at the National Renewable energy Laboratory in Golden Colorado and the University of Colorado Boulder found that they could cover silicon nanoparticles with a rubberlike coating made from aluminum glycerol.
Ban's group#which developed the coating for silicon electrodes called alucone and is currently the only group that can create alucone-coated silicon particles#took high magnification images of the particles in an electron microscope.
and nanoporous graphene a pure form of carbon that's remarkably strong and can efficiently conduct heat and electricity.
And their energy storage abilities may help smooth out the power flow from alternative energy systems such as wind energy. They can power a defibrillator open the emergency slides on an aircraft
Fuel cells use oxygen and hydrogen as a fuel and convert the input chemical energy directly into electricity.
and inorganic-based energy devices such as battery solar cell and self-powered devices that require high temperature processes s
Using the components in 20 million TVS is projected to save 600 million kilowatt-hours of electricity per year worldwide enough electricity to power 50,000 average U s. homes. ee been able to show, cradle to grave,
#New nanocomposites for aerospace and automotive industries The Center for Research in Advanced Materials (CIMAV) has developed reinforced graphite nanoplatelets seeking to improve the performance of solar cell materials.
#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.
The discovery was reported online in the Royal Society of Chemistry's Journal of Materials Chemistry A. Dye-sensitized solar cells have been in development
While they are not nearly as efficient as silicon-based solar cells in collecting sunlight and transforming it into electricity,
dye-sensitized solar cells have advantages for many applications, according to co-lead author Pei Dong, a postdoctoral researcher in Lou's lab."The first is that they're low-cost,
because they can be fabricated in a normal area, "Dong said.""There's no need for a clean room.
The hybrid material solves two issues that have held back commercial application of dye-sensitized solar cells,
Lou's lab built and tested solar cells with nanotube forests of varying lengths The shortest,
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
The new dye-sensitized solar cells were as much as 20 percent better at converting sunlight into power,
Current computer systems represent bits of informationhe 1's and 0's of binary codeith electricity Circuit elements,
They believe it can be used to improve electrical energy storage water filtration and radiofrequency shielding in technology from portable electronics to coaxial cables.
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.
We see anodization as a route to materials for multiple platforms in the next generation of alternative energy devices Tour said.
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,
and aluminum (NCA) offers high enough energy density a measure of the stored electricity in the battery that it works well in large-scale and long-range vehicles including electric cars and commercial aircraft.
Danny Porath, the Etta and Paul Schankerman Professor in Molecular Biomedicine at the Hebrew University of Jerusalem, reports reproducible and quantitative measurements of electricity flow through long molecules made of four
-and it conducts heat and electricity with great efficiency. The global market for graphene is reported to have reached US$9 million this year with most sales concentrated in the semiconductor electronics battery energy and composites.
thus becoming a useful technology in all industrial applications using heat transfer systems such as solar power plants, nuclear power plants, combined-cycle power plants and heating, among other.
This technology provides the capability to modulate neural function by applying programmed pulses of electricity
and reduce the cost of solar cells and increase the capacity and reduce the charging time of batteries he says.
The resulting batteries and solar cells are also mechanically flexible and thus can be integrated with flexible electronics.
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
when consuming a unit amount of electric power which is an important index to compare the energy-efficiency of different lighting devices Shimoi said.
The ability to mold inorganic nanoparticles out of materials such as gold and silver in precisely designed 3-D shapes is a significant breakthrough that has the potential to advance laser technology microscopy solar cells electronics environmental testing
and replace them with synthetic components to create a new generation of solar cells. Professor Evans concludes:"
#Blades of grass inspire advance in organic solar cells Using a biomimicking analog of one of nature's most efficient light-harvesting structures blades of grass an international research team led by Alejandro Briseno of the University of Massachusetts Amherst
has taken a major step in developing long-sought polymer architecture to boost power-conversion efficiency of light to electricity for use in electronic devices.
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.
He says This work is a major advancement in the field of organic solar cells because we have developed
and converting it to electricity. The breakthrough in morphology control should have widespread use in solar cells batteries
and vertical transistors he adds. Briseno explains: For decades scientists and engineers have placed great effort in trying to control the morphology of p-n junction interfaces in organic solar cells.
We report here that we have developed at last the ideal architecture composed of organic single-crystal vertical nanopillars.
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
#Nanoengineering enhances charge transport promises more efficient future solar cells Solar cells based on semiconducting composite plastics 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 deposited from solution by simple and inexpensive methods to form thin and flexible solar cells.
and electricity than had previously been possible using the same materials. This means that the transport of electric charges occurs with a very little energy loss.
and discharge electricity and even be recharged. These talents could make them valuable for powering autonomous MEMS#microelectromechanical machines
Of course much work remains to realize a practical solar cell however the work here is one of the most important steps in that process.
We achieved this using graphene a material that can conduct electricity and interpret touch commands
#Solar cell compound probed under pressure Gallium arsenide Gaas a semiconductor composed of gallium and arsenic is well known to have physical properties that promise practical applications.
In the form of nanowires and nanoparticles it has particular potential for use in the manufacture of solar cells
Silicon nanoparticles such as those in RM 8027 are being studied as alternative semiconductor materials for next-generation photovoltaic solar cells and solid-state lighting,
#Self-organized indium arsenide quantum dots for solar cells Kouichi Yamaguchi is recognized internationally for his pioneering research on the fabrication and applications of'semiconducting quantum dots'(QDS.
Our main interest in QDS is for the fabrication of high efficiency solar cells says Yamaguchi. Step by step we have pushed the limits of'self-organization'based growth of QDS
The realization of an unprecedented QDS density of 5 x 1011 cm-2 in 2011 was one of the major milestones in the development of'self-organization'based semiconducting QDS for solar cells by Yamaguchi
The resulting external quantum efficiency of these solar cell structures in the 900 to 1150 nm wavelength range was higher than devices with the QD layer.
Theoretical studies suggest QDS solar cells could yield conversion efficiencies over 50%explains Yamaguchi. This is a very challenging target
but we hope that our innovative approach will be an effective means of producing such QD based high performance solar cells.
efficiency of intermediate-band solar cells J. Appl. Phys. 112 124515 (2012
#Magnetic field opens and closes nanovesicle Chemists and physicists of Radboud University managed to open and close nanovesicles using a magnet.
#Researchers uncover properties in nanocomposite oxide ceramics for reactor fuel Nanocomposite oxide ceramics have potential uses as ferroelectrics fast ion conductors
In the context of nuclear energy composites have been proposed for the fuel itself as a way for example to improve the basic properties of the material such as the thermal conductivity.
Composites have also been created to store the by-products of the nuclear energy cycle nuclear waste where the different components of the composite can each store a different part of the waste.
Reactor fuel behavior better understood with phonon insights More information: The research is described in a paper out this week in Nature Communications Termination chemistry-driven dislocation structure at Srtio3/Mgo heterointerfaces s
and solar cells crafted with inorganic compound semiconductor micro-rods are moving one step closer to reality thanks to graphene and the work of a team of researchers in Korea.
With nanoparticles, they produced temperature-sensitive devices that transmit electrical energy to the system but do not cause overheating.
electric power is applied and removed for some time, whith the purpose of determining how long it takes to return to its original condition i
and pump protons through a membrane, creating a form of chemical energy. They also know that water can be split into oxygen
Graphene is a super strong, super light, near totally transparent sheet of carbon atoms and one of the best conductors of electricity ever discovered.
can create new sources of clean energy. Her team's discovery may provide future consumers a biologically-inspired alternative to gasoline."
and conduct both heat and electricity. Last year the Rice group created films of overlapping nanoribbons
or conducts electricity. Doping typically effects this change by increasing the number of available electrons,
and electricity it is transparent harder than diamond and extremely strong. But in order to use it to construct electronic switches a material must not only be an outstanding conductor it should also be switchable between on and off states.
and collaborators at Rensselaer Polytechnic institute The latter has a direct impact on the power yield of solar cells.
and his colleagues describe a possible use of graphene strips for instance in solar cells. Ruffieux and his team have noticed that particularly narrow graphene nanoribbons absorb visible light exceptionally well
and are therefore highly suitable for use as the absorber layer in organic solar cells. Compared to normal graphene
and electricity better than any other known materialas potential industrial uses that include flexible electronic displays, high-speed computing, stronger wind turbine blades,
and more-efficient solar cells, to name just a few under development. In the decade since Nobel laureates Konstantin Novoselov and Andre Geim proved the remarkable electronic and mechanical properties of graphene
In digital electronics these transistors control the flow of electricity throughout an integrated circuit and allow for amplification and switching.
#Atomically thin material opens door for integrated nanophotonic circuits A new combination of materials can efficiently guide electricity
at this time organic photovoltaic devices are hindered by low efficiency relative to commercial solar cells in part because quantifying their electrical properties has proven challenging.
"This measurement breakthrough should allow us to more rapidly optimize solar cells,"Richter states.""We're able to look at what happens electronically throughout the entire device.
The larger the difference between the charge lifetime and device transit time greatly improves the likelihood that a photovoltaic device will be a more efficient source of electrical power."
But, when the device does not perform as a"textbook"or"ideal"solar cell then the picture of
Photovoltaic devices, also known as solar cells, produce electrical power when exposed to light, and that technology has enabled a fast-growing industry.
and ultimately more closely connect materials properties with processing methods and solar cell performance.""And since the physical process governing organic photovoltaics is very similar to other organic semiconductors (organic light-emitting diodes, for example,
Understanding how materials grow at the nanoscale level helps scientists tailor them for everything from batteries to solar cells.
or LEDS, and solar technologies.""Heterojunctions are fundamental elements of electronic and photonic devices, "said senior author Xiaodong Xu, a UW assistant professor of materials science and engineering and of physics."
and solar cells to be developed for highly integrated electronic and optical circuits within a single atomic plane."
which is encouraging for optoelectric and photonic applications like solar cells c
#Competition for graphene: Researchers demonstrate ultrafast charge transfer in new family of 2-D semiconductors A new argument has just been added to the growing case for graphene being bumped off its pedestal as the next big thing in the high-tech world by the two-dimensional semiconductors
The separation of photoexcited electrons and holes is essential for driving an electrical current in a photodetector or solar cell."
#Conductive nanofiber networks for flexible unbreakable and transparent electrodes Transparent conductors are required as electrodes in optoelectronic devices, such as touch panel screens, liquid crystal displays, and solar cells.
Examples of applications are large displays, large interactive touch screens, photovoltaic solar panels, light-emitting diode panels, smart phones,
and transfer electricity to a variety of solid surfaces. Today a team led by scientists at USC has turned the study of these bacterial nanowires on its head discovering that the key features in question are not pili as previously believed
or solar cells where this advance is being applied right now. Looking at the bigger picture this technique offers a very promising flexible
The new method should reduce the time nano manufacturing firms spend in trial-and-error searches for materials to make electronic devices such as solar cells organic transistors and organic light-emitting diodes.
He suggests that reaching 5 percent power conversion efficiency would justify the investment for making small flexible solar panels to power devices such as smart phones.
That's nearly the output of a nuclear power station Venkataraman says and it's more dramatic
Doctoral student and first author Tim Gehan says that organic solar cells made in this way can be semitransparent as well so you could replace tinted windows in a skyscraper
and have them all producing electricity during the day when it's needed. And processing is much cheaper and cleaner with our cells than in traditional methods.
Scientists develop pioneering new spray-on solar cells More information: Nano Letters pubs. acs. org/doi/pdf/10.1021/nl502209 9
and rock music improves the performance of solar cells, in research published with Imperial College London. Developing this research further,
or stretched creates a voltage by converting energy from motion into electrical energy, in the form of nanorods.
and form the basis of countless electronic devices such as memory chips photovoltaic cells logic gates and sensors. An interesting alternative to inorganic TFTS (silicon) is organic TFTS (OTFTS)
#Stronger better solar cells: Graphene research on the cusp of new energy capabilities (Phys. org) There remains a lot to learn on the frontiers of solar power research particularly
All of this makes graphene a great candidate for solar cells. In particular its transparency and conductivity mean that it solves two problems of solar cells:
first light needs a good conductor in order to get converted into usable energy; secondly the cell also has to be transparent for light to get through.
Most solar cells on the market use indium tin oxide with a nonconductive glass protective layer to meet their needs.
It's the factor that will keep solar cells expensive in the future whereas graphene could be very cheap.
Although graphene is a great conductor it is not very good at collecting the electrical current produced inside the solar cell
Whether or not it will solve the solar panel problem is yet to be seen and researchers in the field are building up their understanding of how the new material works.
It's a pitfall that could be important to understand in the development of long-lasting solar cells where sun could provide risky heat into the equation.
The material stored a higher amount of electrical energy than commercially available carbon and also had a higher amount of storage compared to graphene
#New material allows for ultra-thin solar cells Extremely thin, semitransparent, flexible solar cells could soon become reality.
At the Vienna University of Technology, Thomas Mueller, Marco Furchi and Andreas Pospischil have managed to create a semiconductor structure consisting of two ultra-thin layers,
creating a designer-material that may be used in future low-cost solar cells. With this advance the researchers hope to establish a new kind of solar cell technology.
Ultra-thin materials, which consist only of one or a few atomic layers are currently a hot topic in materials science today.
"We had already been able to show that tungsten diselenide can be used to turn light into electric energy
But a solar cell made only of tungsten diselenide would require countless tiny metal electrodes tightly spaced only a few micrometers apart.
The heterostructure can now be used to build large-area solar cells. When light shines on a photoactive material single electrons are removed from their original position.
and which voltage leads to an optimum yield of electrical power.""One of the greatest challenges was to stack the two materials,
the solar cell will not work.""Eventually, this feat was accomplished by heating both layers in vacuum and stacking it in ambient atmosphere.
and converted into electric energy. The material could be used for glass fronts, letting most of the light in,
but still creating electricity. As it only consists of a few atomic layers, it is extremely light weight (300 square meters weigh only one gram),
but increase the electrical power o
#Surprise discovery could see graphene used to improve health (Phys. org) chance discovery about the'wonder material'graphene already exciting scientists because of its potential uses in electronics,
which conducts electricity and can be printed by a standard inkjet printer. The graphene-based ink enables cost-effective printed electronics on plastic.
One possibility is to use hybrid solar cells that combine silicon nanowires with low-cost, photoresponsive polymers. The high surface area and confined nature of nanowires allows them to trap significant amounts of light for solar cell operations.
Unfortunately, these thin, needle-like structures are very fragile and tend to stick together when the wires become too long.
One significant problem, notes Wang, is control of the initial stages of nanohole formation crucial period that can often induce defects into the solar cell.
The team analyzed the solar cell activity of their nanohole interfaces by coating them with a semiconducting polymer and metal electrodes.
which impede the solar cell industry, "says Wang.""In addition, this approach can be transferred easily to silicon thin films to develop thin-film siliconolymer hybrid solar cells with even higher efficiency. e
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