#First solar cell made of highly ordered molecular frameworks (Nanowerk News) Researchers at KIT have developed a material suited for photovoltaics.
For the first time, a functioning organic solar cell consisting of a single component has been produced on the basis of metal-organic framework compounds (MOFS.
The material is highly elastic and might also be used for the flexible coating of clothes and deformable components.
"Organic solar cells made of metal-organic frameworks are highly efficient in producing charge carriers. Figure: Wll/KIT) We have opened the door to a new room,
suggest that the excellent properties of the solar cell result from an additional mechanism the formation of indirect band gaps that plays an important role in photovoltaics.
Nature uses porphyrines as universal molecules e g. in hemoglobin and chlorophyll, where these organic dyes convert light into chemical energy.
A metal-organic solar cell produced on the basis of this novel porphyrine-MOF is presented now by the researchers in the journal Angewandte Chemie (Applied Chemistry.
The clou is that we just need a single organic molecule in the solar cell, Wll says.
and take up electric charges. By means of a process developed at KIT, the crystalline frameworks grow in layers on a transparent,
Thanks to their mechanical properties, MOF thin films of a few hundred nanometers in thickness can be used for flexible solar cells or for the coating of clothing material or deformable components.
While the demand for technical systems converting sunlight into electricity is increasing, organic materials represent a highly interesting alternative to silicon that has to be processed at high costs before it can be used for the photoactive layer of a solar cell l
#Chemists devise technology that could transform solar energy storage (Nanowerk News) The materials in most of todays residential rooftop solar panels can store energy from the sun for only a few microseconds at a time.
A new technology developed by chemists at UCLA is capable of storing solar energy for up to several weeks an advance that could change the way scientists think about designing solar cells.
The findings are published June 19 in the journal Science("Long-lived photoinduced polaron formation in conjugated polyelectrolyte-fullerene assemblies".
"The scientists devised a new arrangement of solar cell ingredients, with bundles of polymer donors (green rods) and neatly organized fullerene acceptors (purple, tan.
The new design is inspired by the way that plants generate energy through photosynthesis. Biology does a very good job of creating energy from sunlight,
conventional rooftop solar cells use silicon, a fairly expensive material. There is currently a big push to make lower-cost solar cells using plastics, rather than silicon,
but todays plastic solar cells are relatively inefficient, in large part because the separated positive and negative electric charges often recombine before they can become electrical energy.
Modern plastic solar cells dont have well-defined structures like plants do because we never knew how to make them before,
Tolbert said. But this new system pulls charges apart and keeps them separated for days,
or even weeks. Once you make the right structure you can vastly improve the retention of energy.
The two components that make the UCLA-developed system work are a polymer donor and a nanoscale fullerene acceptor.
the process generates electrical energy. The plastic materials, called organic photovoltaics, are organized typically like a plate of cooked pasta a disorganized mass of long, skinny polymer spaghetti with random fullerene meatballs.
But this arrangement makes it difficult to get current out of the cell because the electrons sometimes hop back to the polymer spaghetti
The researchers are already working on how to incorporate the technology into actual solar cells. Yves Rubin, a UCLA professor of chemistry and another senior co-author of the study,
their designs are intended to be powered grid. When operating off the grid, these systems are not cost-effective,
essentially blocking disconnected, rural villages from using them. Wrights solution offers an alternative to grid power:
Shes designed a village-scale desalination system that runs on solar power. Since her system is powered by the sun,
and provide fracture energy dissipation by stick/slip interactions and frictional sliding of the platelets against each other."
#Sweeping lasers snap together nanoscale geometric grids Down at the nanoscale, where objects span just billionths of a meter,
Now, scientists at the U s. Department of energy's Brookhaven National Laboratory have developed a new technique to rapidly create nano-structured grids for functional materials with unprecedented versatility."
"We can fabricate multi-layer grids composed of different materials in virtually any geometric configuration,
"The results published online June 23 in the journal Nature Communications could transform the manufacture of high-tech coatings for anti-reflective surfaces, improved solar cells,
"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.
"To make these two-dimensional grids functional, the scientists converted the polymer base into other materials.
and overlap shapes the grid. We then apply the functional materials after each layer forms.
"For example, a single layer of platinum nanowires conducts electricity in only one direction, but a two-layer mesh conducts uniformly in all directions."
however, will require extremely low-power sensors that can run for months without battery changes or, even better,
that can extract energy from the environment to recharge. Last week, at the Symposia on VLSI Technology And circuits, MIT researchers presented a new power converter chip that can harvest more than 80 percent of the energy trickling into it
even at the extremely low power levels characteristic of tiny solar cells. Previous experimental ultralow-power converters had efficiencies of only 40 or 50 percent.
Moreover, the researcherschip achieves those efficiency improvements while assuming additional responsibilities. Where its predecessors could use a solar cell to either charge a battery
or directly power a device, this new chip can do both, and it can power the device directly from the battery.
All of those operations also share a single inductor the chip main electrical component which saves on circuit board space
the chip power consumption remains low. e still want to have battery-charging capability, and we still want to provide a regulated output voltage,
Ups and downs The circuit chief function is to regulate the voltages between the solar cell, the battery,
If the battery operates for too long at a voltage that either too high or too low, for instance, its chemical reactants break down,
since the rate at which it dissipates energy as heat is proportional to the square of the current.
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,
because there a fixed amount of energy that consumed by doing the work, says Brett Miwa,
the new design helps solve many key problems affecting mobile displays such as how to provide an always-on display function without requiring more frequent battery charging
Extending Power and Saving Energy Depending on how the display is used, the power savings can exceed current backlit technologies tenfold.
In an engineering first, Cui and his colleagues used lithium-ion battery technology to create one low-cost catalyst that is capable of driving the entire water-splitting reaction.'
'Our group has pioneered the idea of using lithium-ion batteries to search for catalysts, 'Cui said.'
A conventional water-splitting device consists of two electrodes submerged in a water-based electrolyte.
But in 2014, Stanford chemist Hongjie Dai developed a water splitter made of inexpensive nickel and iron that runs on an ordinary 1. 5-volt battery.
'This bifunctional catalyst can split water continuously for more than a week with a steady input of just 1. 5 volts of electricity.
'In conventional water splitters, the hydrogen and oxygen catalysts often require different electrolytes with different phone acidic,
'For practical water splitting, an expensive barrier is needed to separate the two electrolytes, adding to the cost of the device,
'But our single-catalyst water splitter operates efficiently in one electrolyte with a uniform ph.'Wang
'At first the device only needed 1. 56 volts of electricity to split water, but within 30 hours we had to increase the voltage nearly 40 percent.
'Marriage of batteries and catalysis To find catalytic material suitable for both electrodes, the Stanford team borrowed a technique used in battery research called lithium-induced electrochemical tuning.
The idea is to use lithium ions to chemically break the metal oxide catalyst into smaller and smaller pieces.'
The technique has been used in battery research for many years, but it's a new approach for catalysis. The marriage of these two fields is very powerful
have developed a new method to see inside battery-like devices known as supercapacitors at the atomic level.
where they can be used alongside batteries to enhance a vehicle performance. By using a combination of nuclear magnetic resonance (NMR) spectroscopy
They are used also in flashes in mobile phones and as a complementary technology to batteries in order to boost performance.
when placed alongside a battery in an electric car, a supercapacitor is useful when a short burst of power is required,
such as when overtaking another car, with the battery providing the steady power for highway driving. upercapacitors perform a similar function to batteries
and the paper lead author. heye much better at absorbing charge than batteries, but since they have much lower density,
and that might make them a high-power alternative to batteries. At its most basic level, a battery is made of two metal electrodes (an anode and a cathode) with some sort of solution between them (electrolyte.
When the battery is charged, electrolyte ions are stored in the anode. As the battery discharges, electrolyte ions leave the anode
and move across the battery to chemically react with the cathode. The electrons necessary for this reaction travel through the external circuit,
generating an electric current. A supercapacitor is similar to a battery in that it can generate and store electric current,
but unlike a battery, the storage and release of energy does not involve chemical reactions: instead, positive and negative electrolyte ions simply tickto the surfaces of the electrodes when the supercapacitor is being charged.
When a supercapacitor is being discharged to power a device, the ions can easily opoff the surface
and move back into the electrolyte. The reason why supercapacitors charge and discharge so much faster is that the tickingand oppingprocesses happen much faster than the chemical reactions at work in a battery. o increase the area for ions to stick to,
we fill the carbon electrode with tiny holes, like a carbon sponge, said Griffin. ut it hard to know what the ions are doing inside the holes within the electrode we don know exactly what happens
when they interact with the surface. In the new study, the researchers used NMR to look inside functioning supercapacitor devices to see how they charge and store energy.
They also used a type of tiny weighing scale called an electrochemical quartz crystal microbalance (EQCM) to measure changes in mass as little as a millionth of a gram.
By taking the two sets of information and putting them together, the researchers were able to build a precise picture of
what happens inside a supercapacitor while it charges. n a battery, the two electrodes are different materials,
so different processes are said at work Griffin. n a supercapacitor, the two electrodes are made of the same porous carbon sponge,
and see in detail exactly how the energy is stored, said Griffin. n the future we can look at how changing the size of the holes in the electrode
we can tailor the properties of both components to maximise the amount of energy that is stored.
"Quantum dots, which have use in diverse applications such as medical imaging, lighting, display technologies, solar cells, photocatalysts, renewable energy and optoelectronics, are typically expensive and complicated to manufacture.
or chemical environment to provide unique functionality in a wide range of applications from energy to medicine.
The interaction between liquid crystal molecules and plasmon waves on the nanostructured metallic surface played the key role in generating the polarization-independent
This method demands less energy and is cheaper and the synthesized materials have some incredible new properties.
and manufacture of superconductors or high-efficiency solar cells and light sensors, said leader of the research,
#Nanogenerator harvests power from rolling tires A group of University of Wisconsin-Madison engineers and a collaborator from China have developed a nanogenerator that harvests energy from a car's rolling tire friction.
An innovative method of reusing energy, the nanogenerator ultimately could provide automobile manufacturers a new way to squeeze greater efficiency out of their vehicles.
which is the first of its kind, in a paper published May 6, 2015, in the journal Nano Energy("Single-electrode triboelectric nanogenerator for scavenging friction energy from rolling tires").
Xudong Wang has developed a new way to harvest energy from rolling tires. The nanogenerator relies on the triboelectric effect to harness energy from the changing electric potential between the pavement and a vehicle's wheels.
The triboelectric effect is the electric charge that results from the contact or rubbing together of two dissimilar objects.
Wang says the nanogenerator provides an excellent way to take advantage of energy that is usually lost due to friction."
"The friction between the tire and the ground consumes about 10 percent of a vehicle's fuel,
"That energy is wasted. So if we can convert that energy, it could give us very good improvement in fuel efficiency."
"The nanogenerator relies on an electrode integrated into a segment of the tire. When this part of the tire surface comes into contact with the ground,
the friction between those two surfaces ultimately produces an electrical charge-a type of contact electrification known as the triboelectric effect.
The movement of electrons caused by friction was able to generate enough energy to power the lights
supporting the idea that energy lost to friction can actually be collected and reused.""Regardless of the energy being wasted,
we can reclaim it, and this makes things more efficient, "Wang says.""I think that's the most exciting part of this,
how to save the energy from consumption.""The researchers also determined that the amount of energy harnessed is directly related to the weight of a car,
as well as its speed. Therefore the amount of energy saved can vary depending on the vehicle -but Wang estimates about a 10-percent increase in the average vehicle's gas mileage given 50-percent friction energy conversion efficiency."
"There's big potential with this type of energy, "Wang says.""I think the impact could be huge."
"Source: University of Wisconsin-Madiso o
#Graphene flexes its electronic muscles Flexing graphene may be the most basic way to control its electrical properties, according to calculations by theoretical physicists at Rice university and in Russia.
The Rice lab of Boris Yakobson in collaboration with researchers in Moscow found the effect is pronounced
and Energy technology UMSICHT in Oberhausen and the Institute for Chemical Technology ICT in Pfinztal. The technology came about during one of Fraunhofers internal preliminary research projects and through individual projects with industrial partners.
nighttime conversion (Nanowerk News) A University of Texas at Arlington materials science and engineering team has developed a new energy cell that can store large-scale solar energy even
The innovation is an advancement over the most common solar energy systems that rely on using sunlight immediately as a power source.
the ability to store solar energy and use it as a renewable alternative provides a sustainable solution to the problem of energy shortage.
It also can effectively harness the inexhaustible energy from the sun."Dong Liu (left), Zi Wei (center) and Fuqiang Liu, an assistant professor in the UT Arlington Materials science and engineering Department.
and consume energy.""Dr. Liu and his colleagues are working to help us shape a more sustainable future
and use one of the larger sources of energy available to us-the sun, "Behbehani said.
said a major drawback of current solar technology is the limitation on storing energy under dark conditions."
#New lithium ion battery is safer, tougher, and more powerful Lithium ion batteries (LIBS) are a huge technological advancement from lead acid batteries
which have existed since the late 1850. Thanks to their low weight, high energy density and slower loss of charge when not in use, LIBS have become the preferred choice for consumer electronics.
Lithium-ion cells with cobalt cathodes hold twice the energy of a nickel-based battery and four times that of lead acid.
Despite being a superior consumer battery, LIBS still have some drawbacks. Current manufacturing technology is reaching the theoretical energy density limit for LIBS
and overheating leading to thermal runaway i e. enting with flameis a serious concern. South korean researchers at the Center for Self-assembly and Complexity, Institute for Basic Science (IBS), Department of chemistry and Division of Advanced Materials science at Pohang University, have created a new LIB made from a porous solid
which greatly improves its performance as well as reducing the risks due to overheating("Solid lithium electrolytes based on an organic molecular porous solid").
These types of batteries, in all of their different lithium-anode combinations, continue to be an essential part of modern consumer electronics
The Korean team tried a totally new approach in making the batteries. According to Dr. Kimoon Kim at IBS, e have investigated already high
and highly anisotropic directionally dependent proton conducting behaviors in porous CB 6 for fuel cell electrolytes.
It is possible for this lithium ion conduction following porous CB 6 to be safer than existing solid lithium electrolyte-based organic-molecular porous-materials utilizing the simple soaking method
investigation of novel electrolytes is necessary in order. The new battery is built from pumpkin-shaped molecules called cucurbit 6 uril (CB 6)
which are organized in a honeycomb-like structure. The molecules have an incredibly thin 1d-channel,
The physical structure of the porous CB 6 enables the lithium ions to battery to diffuse more freely than in conventional LIBS
and exist without the separators found in other batteries. In tests the porous CB 6 solid electrolytes showed impressive lithium ion conductivity.
To compare this to existing battery electrolytes, the team used a measurement of the lithium transference number (tli)
+which was recorded at 0. 7-0. 8 compared to 0. 2-0. 5 of existing electrolytes.
They also subjected the batteries to extreme temperatures of up to 373 K (99.85°C), well above the 80°C typical upper temperature window for exiting LIBS.
In the tests, the batteries were cycled at temperatures between 298 K and 373 K (24.85°C and 99.85°C) for a duration of four days and after each cycle the results showed no thermal runaway and hardly any change in conductivity.
Various conventional liquid electrolytes can incorporate in a porous CB 6 framework and converted to safer solid lithium electrolytes.
Additionally, electrolyte usage is limited not to use only in LIBS, but a lithium air battery potentially feasible.
What makes this new technique most exciting is that it is a new method of preparing a solid lithium electrolyte
which starts as a liquid but no post-synthetic modification or chemical treatment is needed t
#Visualizing RNAI at work University of Tokyo and Kyoto University researchers have revealed the molecular mechanism of RNA interference (RNAI), the phenomenon by
which the synthesis of a specific protein is inhibited, by real time observation of target RNA cleavage at the single-molecule level.
In the beginning, the idea was to develop a radioactivity sensor for inside a nuclear power station says Tijmen Euser from the Max Planck Institute in Erlangen.
By wrapping the fibre around the reactor, fibre-optic sensors could probe the entire surface of a reactor.
It turns out, however, that radioactive radiation darkens the interior of conventional glass fibres so that light can no longer propagate therein,
The result of the study is published in the journal Nature Communications("Structural basis for catalytically restrictive dynamics of a high-energy enzyme state".
So-called high-energy states in enzymes are regarded as necessary for catalysing of chemical reactions. A high-energy level is a protein structure only occurring temporarily and for a short period of time;
and these factors collaborate until its state becomes invisible to traditional spectroscopic techniques. The Ume researchers have managed to find a way to maintain a high-energy state in the enzyme, adenylate kinase,
by mutating the protein.""Thanks to this enrichment, we have been able to study both structure and dynamics of this state.
The study shows that enzymatic high-energy states are necessary for chemical catalysis, "says Magnus Wolf-Watz, research group leader at the Department of chemistry.
"Research on Bioenergy is an active field at Ume University. An important, practical application of the new knowledge can be enzymatic digestion of useful molecules from wooden raw materials,
discrete states comparable to the energy level of a single atom. The molecule at the tip of the microscope functions like a beam balance,
where they create clothing that kills bacteria, conducts electricity, wards off malaria, captures harmful gas and weaves transistors into shirts and dresses.
With ultrathin solar panels for trim and a USB charger tucked into the waist, the Southwest-inspired garment captured enough sunshine to charge cell phones
and emit light energy is such that it can make itself--and, in applications, other very small things--appear 10,000 times as large as its physical size."
amplifying itself as the surrounding environment manipulates the physical properties of its wave energy. The researchers took advantage of this by creating an artificial material in
Much as a very thin string on a guitar can absorb a large amount of acoustic energy from its surroundings
In addition, Yu envisions simply letting the resonator emit that energy in the form of infrared light toward the sky,
cyanobacteria suck in huge amounts of carbon dioxide from the environment and convert it into other materials, such as biomass.
Scientists the world over currently are developing ways to take advantage of these natural processes to create new forms of energy.
#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.
Professor of Chemistry, could have applications in areas ranging from consumer electronics to solar panels. This is really a fundamental Discovery day said.
and lead to faster transistors, cheaper solar cells, new types of sensors and more efficient bioelectric sensory devices.
and it can conduct electricity as well as copper, carrying electrons with almost no resistance even at room temperature, a property known as ballistic transport.
the jolt of energy can kick one of its electrons up to an excited state and create a charge distribution imbalance.
it takes a great deal of energy to excite electrons from one level to another--and only displays photocatalytic properties under ultraviolet light.
decreasing the amount of energy necessary to activate the photocatalyst. When the researchers mixed the hybrid nanoparticles with BPA solution under an artificial visible light source
At its most basic level, your smart phone's battery is powering billions of transistors using electrons to flip on and off billions of times per second.
they are too energy-hungry and unwieldy to integrate into computer chips. Duke university researchers are now one step closer to such a light source.
Energy trapped on the surface of the nanocube in this fashion is called a plasmon. The plasmon creates an intense electromagnetic field between the silver nanocube
and a thin sheet of gold placed a mere 20 atoms away. This field interacts with quantum dots--spheres of semiconducting material just six nanometers wide--that are sandwiched in between the nanocube and the gold.
foldable and lightweight energy storage device that provides the building blocks for next-generation batteries needed to power wearable electronics and implantable medical devices (ACS Central Science,"Self-Assembled Multifunctional Hybrids:
Toward Developing High-performance Graphene-Based Architectures for Energy storage devices"."The conundrum researchers have faced in developing miniature energy storage devices,
such as batteries and supercapacitors, has been figuring out how to increase the surface area of the device, to store more charge,
without making it larger. mong all modern electronic devices, portable electronics are some of the most exciting,
and will be more lightweight than traditional batteries used in present day electronics. The ISEM study has been supported financially by the Automotive Australia 2020 CRC as part of its research into electric vehicles.
and plays crucial role for design of next generation electric vehicles A key to unlocking the electric vehicle capability is a lightweight and powerful battery pack. ur simple fabrication method of eco-friendly materials
with increased performance has great potential to be scaled up for use supercapacitor and battery technology. Our next step is to use this material to fabricate flexible wearable supercapacitors with high power density and energy density as well as large scale supercapacitors for electric vehicles. u
#Smart hydrogel coating creates'stick-slip'control of capillary action Coating the inside of glass microtubes with a polymer hydrogel material dramatically alters the way capillary forces draw water into the tiny structures,
which the system creates an energy barrier to further motion through elasto-capillary deformation, and then lowers the barrier through diffusive softening,
and it uses far less energy. The plasmon-trick For this sleight of hand the researchers led by Leuthold and his doctoral student Christian Haffner
who contributed to the development of the modulator, use a technical trick. In order to build the smallest possible modulator they first need to focus a light beam
the light is turned first into so-called surface-plasmon-polaritons. Plasmon-polaritons are a combination of electromagnetic fields
and electrons that propagate along a surface of a metal strip. At the end of the strip they are converted back to light once again.
The advantage of this detour is that plasmon-polaritons can be confined in a much smaller space than the light they originated from.
but rather plasmon-polaritons that are sent through an interferometer that is only half a micrometer wide.
and hence the velocity of the plasmons in one arm of the interferometer can be varied,
After that, the plasmons are reconverted into light, which is fed into a fibre optic cable for further transmission.
Faster communication with less energy The modulator built by Leuthold and his colleagues has several advantages at once."
and that thus modulates the plasmons inside the interferometer. As such a modulator is much smaller than conventional devices it consumes very little energy-only a few thousandth of Watts at a data transmission rate of 70 Gigabits per second.
This corresponds to merely a hundredth of the consumption of commercial models. In that sense it contributes to the protection of the environment
given that the amount of energy used worldwide for data transmission is considerable-after all, there are modulators in every single fibre optic line.
which leads to an increasing energy consumption. A hundredfold energy saving would, therefore, be more than welcome.""Our modulator provides more communication with less energy,
"as the ETH professor puts it in a nutshell. At present the reliability of the modulator is being tested in long term trials,
which is a crucial step towards making it fit for commercial use e
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