and polymers that exist today. rom a fundamental-science point of view our discovery is intriguing because the threads we formed have a structure that has never been seen beforeays study leader John V. Badding a professor of chemistry at Penn State.
so that when we release the pressure very slowly an orderly polymerization reaction happens that forms the diamond-core nanothread.
#3, 600 crystals in wearable skin monitor health 24/7 A new wearable medical device that uses up to 3600 liquid crystals can quickly let you know
Metals are not suitable and initially the ETH team was had unaware it found the material that others had been looking for. e observed something strange in our measurements with the graphene sandwich construction that we were not able to explainsays Varlet.
To produce the sandwich construction Varlet enclosed the double layer of graphene in two layers of boron nitride a material otherwise used for lubrication
#New polymer makes solar cells more efficient Solar cells made from polymers have the potential to be cheap and lightweight
A polymer is a type of large molecule that forms plastics and other familiar materials. he field is rather immature it s in the infancy stagesays Luping Yu a professor in chemistry at the University of Chicago.
Now a team of researchers led by Yu has identified a new polymer that allows electrical charges to move more easily through the cell boosting electricity production. olymer solar cells have great potential to provide low-cost lightweight
The active regions of such solar cells are composed of a mixture of polymers that give and receive electrons to generate electrical current
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.
when an optimal amount of PID2 was added the highest ever for solar cells made up of two types of polymers with fullerene
The group which includes researchers at the Argonne National Laboratory is now working to push efficiencies toward 10 percent a benchmark necessary for polymer solar cells to be viable for commercial application.
The standard mechanism for improving efficiency with a third polymer is by increasing the absorption of light in the device.
when PID2 was added charges were transported more easily between polymers and throughout the cell. 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.
PID2 has energy levels in between the other two and acts as an intermediary in the process. t s like a stepyu says. hen it s too high it s hard to climb up
but if you put in the middle another step then you can easily walk up. he addition of PID2 caused the polymer blend to form fibers
and for displaying patterns on large polymer sheets. For example Halas and colleagues published a study in Advanced Materials in August about an aluminum-based CMOS-compatible photodetector technology for color sensing.
In addition University of Illinois at Urbana-Champaign co-principal investigator John Rogers and colleagues published a proof-of-concept study in PNAS in August about new methods for creating flexible black-and-white polymer displays
#These LEGO-inspired ceramics won t shatter California Institute of technology rightoriginal Studyposted by Brian Bell-Caltech on September 12 2014scientists are on the way to developing the perfect ceramic material:
In a paper published in the journal Science the researchers explain how they used the method to produce a ceramic (e g. a piece of chalk
You can create materials by design. he researchers use a direct laser writing method called two-photon lithography to ritea three-dimensional pattern in a polymer by allowing a laser beam to crosslink
and harden the polymer wherever it is focused. The parts of the polymer that were exposed to the laser remain intact
while the rest is dissolved away revealing a three-dimensional scaffold. That structure can then be coated with a thin layer of just about any kind of material#a metal an alloy a glass a semiconductor etc.
Then the researchers use another method to etch out the polymer from within the structure leaving a hollow architecture.
The applications of this technique are practically limitless Greer says. Since pretty much any material can be deposited on the scaffolds the method could be particularly useful for applications in optics energy efficiency and biomedicine.
After the patterning step they coated the polymer scaffold with a ceramic called alumina (i e. aluminum oxide) producing hollow-tube alumina structures with walls ranging in thickness from 5 to 60 nanometers and tubes from 450 to 1380 nanometers in diameter.
That was not surprising given that ceramics especially those that are porous are brittle. However compressing lattices with a lower ratio of wall thickness to tube diameter#where the wall thickness was only 10 nanometers#produced a very different result. ou deform it
and they could still recover. o understand why consider that most brittle materials such as ceramics silicon
#This smartphone case is 3x harder than steel Yale university Posted by Jim Shelton-Yale on September 5 2014a new smartphone case is lightweight thin harder than steel
With this technique which Schroers calls thermoplastic forming BMGS can be shaped like plastics. As a consequence thermoplastic forming BMGS don t require massive amounts of energy.
From there Schroers focused on producing BMGS in sheets. That form he reasoned is the most conducive to practical manufacturing applications. eveloping a fabrication method for BMG sheets has been extremely difficult
which can be carried out as easily as the process for blow-molding plastics. Seeing the commercial potential for his technique Schroers launched his own company Supercool Metals.
The company has exclusive licensing rights to the technology which is owned by Yale. e re taking a great scientific idea and making it viable in the larger worldsays Tobias Noesekabel Supercool Metals intern and an MBA candidate at the Yale School of management.
Until now Schroers has focused on smaller-scale specialty production items including watch components and sensors. Smartphone cases were a natural
He and his team produce the cases by blow-molding BMG sheets into brass molds to precise specifications.
Microtubules are string-like protein polymers that together with kinesin transport cargo around the cells.
and DNA the assembly of nanotechnological components or small organic polymers or the chemical alteration of carbon nanotubes. e need to continue to optimize the system
in order to achieve the goal of pouring sugar into a stainless steel vat of bioengineered yeast and skimming off specific opioids at the end of the process.
professor at Stanford university. his is the first time anyone has used non-precious metal catalysts to split water at a voltage that low.
It s quite remarkable because normally you need expensive metals like platinum or iridium to achieve that voltage. n addition to producing hydrogen the new water splitter could be used to make chlorine gas and sodium hydroxide an important industrial chemical according to Dai.
and long durabilitydai says. hen we found out that a nickel-based catalyst is as effective as platinum it came as a complete surprise. tanford graduate student Ming Gong co-lead author of the study made the discovery. ing discovered a nickel-metal
The lowinginfrared light is guided to the edge of the plastic where it is converted to electricity by thin strips of photovoltaic solar cells. ecause the materials do not absorb
The setup adds a printed pinhole screen sandwiched between two layers of clear plastic to an ipod display to enhance image sharpness.
and it s the only metal shown to be able to reduce CO2 to useful hydrocarbonssays senior author Tayhas Palmore professor of engineering at Brown University. here was some indication that
To overcome this challenge the team developed a special blend of polyurethane and an adhesive.
The liquid polymer filled the mold but as it cured the material shrunk slightly. This allowed the pillars to release easily.
The team demonstrated the nanopillars could stick to plastics fabric paper and metal and they anticipate that the arrays will also transfer easily to glass and leather.
This work is reported in Advanced Materials. The university is pursuing patent protection for the intellectual property
and hydrogel#a water-based polymer gel that provides structural support #thus learingthe tissue but leaving its three-dimensional architecture intact for study.
which Yakobson says keeps them from slipping into a less-stable Peierls distortion. eierls said one-dimensional metals are unstable and must become semiconductors
and the metal state. akobson explains that ZPV is a manifestation of quantum uncertainty which says atoms are always in motion. t s more a blur than a vibrationhe says. e can say carbyne represents the uncertainty principle in action
and may apply equally to other one-dimensional chains subject to Peierls distortions including conducting polymers and charge/spin density-wave materials.
By coupling electromagnetic waves with surface plasmons the oscillating electrons found at the surface of metals researchers were able to squeeze light into nanosized spaces
and pigments that does the photosynthetic heavy lifting. It also the only known natural enzyme that uses solar energy to split water into hydrogen and oxygen.
which uses no metals or toxic materials, for use in power plants, where it could make the energy grid more resilient and efficient by creating a large-scale way to store energy for use as needed. he batteries last for about 5,
While previous battery designs have used metals or toxic chemicals, Narayan and Prakash wanted to find an organic compound that could be dissolved in water.
Barron and graduate student Yen-Tien Lu, the study lead author, replaced a two-step process that involved metal deposition
and turns the neat trick of converting gaseous carbon dioxide into solid polymer chains that nestle in the pores. obody s ever seen a mechanism like thistour says. ou ve got to have that nucleophile (the sulfur
or nitrogen atoms) to start the polymerization reaction. This would never work on simple activated carbon; the key is that the polymer forms
and provides continuous selectivity for carbon dioxide. ethane ethane and propane molecules that make up natural gas may try to stick to the carbon
but the growing polymer chains simply push them off he says. The researchers treated their carbon source with potassium hydroxide at 600 degrees Celsius to produce the powders with either sulfur
After heating it to 600 degrees C for the one-step synthesis from inexpensive industrial polymers the final carbon material has a surface area of 2500 square meters per gram
#Scientists are first to detect exciton in metals University of Pittsburgh rightoriginal Studyposted by Joe Miksch-Pittsburgh on June 2 2014humans have used reflection of light from a metal mirror on a daily basis for thousands of years
For the first time researchers have detected the exciton a fundamental particle of light-matter interaction in metals. Physicists describe physical phenomena in terms of interactions between fields
and matter interact at the surface of a silver crystal. They observe for the first time an exciton in a metal.
Excitons particles of light-matter interaction where light photons become transiently entangled with electrons in molecules
The optical and electronic properties of metals cause excitons to last no longer than approximately 100 attoseconds (0. 1 quadrillionth of a second.
Such short lifetimes make it difficult for scientists to study excitons in metals but it also enables reflected light to be a nearly perfect replica of the incoming light.
and Petek and his team experimentally discovered that the surface electrons of silver crystals can maintain the excitonic state more than 100 times longer than the bulk metal enabling the excitons in metals to be captured experimentally by a newly developed multidimensional coherent spectroscopic technique.
The ability to detect excitons in metals sheds light on how light is converted to electrical
and chemical energy in plants and solar cells and in the future it may enable metals to function as active elements in optical communications.
In other words it may be possible to control how light is reflected from a metal. The paper appears online in Nature Physics.
The transducer is made of a mixture of a spongy plastic called polydimethylsiloxane, or PDMS, and carbon nanotubes.
Though ultrasound detectors existncluding those used in medical imaginghe researchers made their own sensitive one in the form of a microscopic plastic ring known as a microring resonator.
Sandwiched between the two electrodes is a polymer film that acts as a reservoir of charged ions similar to the role of the electrolyte paste in a battery.
When the electrodes are pressed together the polymer oozes into the tiny pores in much the same way that melted cheese soaks into the nooks and crannies of the bread in a panini.
When the polymer cools and solidifies it forms an extremely strong mechanical bond. he biggest problem with designing load-bearing supercaps is preventing them from delaminatingsays Westover. ombining nanoporous material with the polymer electrolyte bonds the layers together tighter than superglue. he use
of silicon in structural supercapacitors is suited best for consumer electronics and solar cells but Pint and Westover are confident that the rules that govern the load-bearing character of their design will carry over to other materials such as carbon nanotubes and lightweight porous metals like aluminum.
The intensity of interest in ultifunctionaldevices of this sort is clear: The US Department of energy s Advanced Research Project Agency for Energy is investing $8. 7 million in research projects that focus specifically on incorporating energy storage into structural materials.
They have filed also a patent for this technology due to its commercial potential. e use a simple polymer-based film to remove the impurities
associate professor in the department of chemical engineering. t is all polymer and we are able to get performances comparable to really expensive materials such as mixed matrix membranes
The membrane that Grunlan and Wilhite have developed is a layer-by-layer polymer coating that is comprised of alternating individual layers of common, low-cost polyelectrolytes.
says Grunlan. xcept for a sheet of metal, nothing has higher selectivity than our coating.
IBM OLDEN GATECHIP One of these efforts is IBM Synapse Projecthort for Systems of Neuromorphic Adaptive Plastic Scalable Electronics.
#Renewable cellulose crystals are as stiff as steel The same tiny cellulose crystals that give trees
Calculations using precise models based on the atomic structure of cellulose show the crystals have a stiffness of 206 gigapascals
which is comparable to steel says Pablo D. Zavattieri a Purdue University assistant professor of civil engineering. his is a material that is showing really amazing propertieshe says. t is abundant renewable and produced as waste in the paper industry. indings
are detailed in the journal Cellulose. t is very difficult to measure the properties of these crystals experimentally
and predict the behavior of individual crystals the interaction between them and their interaction with other materialszavattieri says. his is important for the design of novel cellulose-based materials as other research groups are considering them for a huge variety of applications ranging from electronics
and medical devices to structural components for the automotive civil and aerospace industries. he cellulose nanocrystals represent a potential green alternative to carbon nanotubes for reinforcing materials such as polymers and concrete.
Cellulose biomaterials might be used to create biodegradable plastic bags textiles and wound dressings; flexible batteries made from electrically conductive paper;
another process to use the leftover cellulose to make a composite materialmoon says. he cellulose crystals are more difficult to break down into sugars to make liquid fuel.
so that it binds strongly with a reinforcing polymer to make a new type of tough composite material
They have learned to increase the power output by applying micron-scale patterns to the polymer sheets.
and even distilled waterâ##and a patterned polymer surface. Their latest paper published in the journal ACS Nano described harvesting energy from the touch pad of a laptop computer.
They are now using a wide range of materials including polymers fabrics and even papers.
The generators can be made from nearly transparent polymers allowing their use in touch pads and screens.
#Car paint with graphene gets ice off radar domes Rice university rightoriginal Studyposted by Mike Williams-Rice on December 18 2013ribbons of ultrathin graphene combined with polyurethane paint meant for cars can keep ice off of sensitive military
He found the solution in a Houston auto parts store. bought some polyurethane car paint
and GNRS and coated our samples it had all the properties we needed. ab samples up to two square feet were assembled using a flexible polymer substrate polyimide
which was spray-coated with polyurethane paint and allowed to dry The coated substrate was then put on a hotplate to soften the paint
Tour says the researchers have tried also putting GNRS under the polyurethane paint with good results.
It consists of plastic for the housing a conductive coil and a magnet. The challenge is coming up with a design
and biomolecular engineering to come up with a viscous blend of strontium ferrite. It s not the first time a consumer electronic device was printed in Lipson s lab. Back in 2009 Malone
#DNA helps nanoparticle crystals self-assemble Northwestern University rightoriginal Studyposted by Megan Fellman-Northwestern on December 2 2013using the same structure found in nature researchers have built the first near-perfect single crystals
and DNA. ingle crystals are the backbone of many things we rely onâ##diamonds for beauty as well as industrial applications sapphires for lasers
and silicon for electronicssays nanoscientist Chad A. Mirkin. he precise placement of atoms within a well-defined lattice defines these high-quality crystals. ow we can do the same with nanomaterials
research group developed the ecipefor using nanomaterials as atoms DNA as bonds and a little heat to form tiny crystals.
This single-crystal recipe builds on superlattice techniques Mirkin s lab has been developing for nearly two decades.
and shape of crystals they can build. The team worked with gold nanoparticles but the recipe can be applied to a variety of materials with potential applications in the fields of materials science photonics electronics
and catalysis. A single crystal has order: its crystal lattice is continuous and unbroken throughout. The absence of defects in the material can give these crystals unique mechanical optical and electrical properties making them very desirable.
In the study strands of COMPLEMENTARY DNA act as bonds between disordered gold nanoparticles transforming them into an orderly crystal.
We are learning so many rules for calculating things that other people cannot compute in atoms in atomic crystals. he ratio affects the energy of the faces of the crystals
and result in a sphere not a faceted crystal she explained. With the correct ratio the energies fluctuate less
and result in a crystal every time. magine having a million balls of two colors some red some blue in a container
and link togetherhe says. hey beautifully assemble into a three-dimensional crystal that we predicted computationally
and realized experimentally. o achieve a self-assembling single crystal in the lab the research team reports taking two sets of gold nanoparticles outfitted with COMPLEMENTARY DNA
The very slow cooling process encouraged the single stranded-dna DNA to find its complement resulting in a high-quality single crystal approximately three microns wide. he process gives the system enough time
There s no reason we can t grow extraordinarily large single crystals in the future using modifications of our techniquesays Mirkin who also is a professor of medicine chemical and biological engineering biomedical engineering and materials science and engineering and director of the university s International Institute for Nanotechnology.
and Fermi-edge singularities a process known to occur in metals. The team previously reported the first observation of superfluorescence in a solid-state system by strongly exciting semiconductor quantum wells in high magnetic fields.
The secret is a stretchy polymer that coats the electrode binds it together and spontaneously heals tiny cracks that develop during battery operation. elf-healing is very important for the survival and long lifetimes of animals
so they will have a long lifetime as well. ang developed the self-healing polymer in the lab of Zhenan Bao a professor of chemical engineering at Stanford
For the battery project Chao added tiny nanoparticles of carbon to the polymer so it would conduct electricity. e found that silicon electrodes lasted 10 times longer
when coated with the self-healing polymer which repaired any cracks within just a few hoursbao says. heir capacity for storing energy is in the practical range now
Attached to each of the cyclic peptides are two different types of polymers which tend to de-mix
and polymers. anus nanotubes are a versatile platform for the design of exciting materials which have a wide range of application from membranesâ##for instance for the purification of waterâ##to therapeutic uses including the development of new drug systems. ource:
#Crystal structure could push the limits of solar cells University of Pennsylvania right Original Studyposted by Evan Lerner-Pennsylvania on November 13 2013 A new model for solar cell construction may ultimately make them less expensive easier to manufacture
The resulting crystal would ideally have the structure of the parent but with elements from the second material in key locations enabling it to absorb visible light. he design challengesays Peter K. Davies chair of the department of materials science and engineering as to identify materials that could retain their polar properties while simultaneously absorbing visible light.
Most light absorbing materials have a symmetrical crystal structure meaning their atoms are arranged in repeating patterns up down left right front and back.
A perovskite crystal has the same cubic lattice of metal atoms but inside of each cube is an octahedron of oxygen atoms
when you have a material with two metals and oxygen. It's not something we had to architect ourselves. fter several failed attempts to physically produce the specific perovskite crystals they had theorized the researchers succeeded with a combination of potassium niobate the parent polar material and barium nickel niobate
which contributes to the final product's bandgap. The researchers used X-ray crystallography and Raman scattering spectroscopy to ensure they had produced the crystal structure and symmetry they intended.
They also investigated its switchable polarity and bandgap showing that they could indeed produce a bulk photovoltaic effect with visible light opening the possibility of breaking the Shockley-Queisser limit.
With reflective pigments mixing blue and yellow yields green; however with emissive light mixing such complementary colors yields white.
Until recently the preparation of phosphor materials was more an art than a science based on finding crystal structures that act as hosts to activator ions
and stabilize the sulfur the researchers used amylopectin a polysaccharide that s a main component of corn starch. he corn starch can effectively wrap the graphene oxide-sulfide composite through the hydrogen bonding to confine the polysulfide among the carbon layerssays Hao Chen
to make lithium-sulfur cathodes by synthesizing a nanocomposite consisting of sulfur coated with a common inexpensive conductive polymer called polyaniline and
Similar sulfur-polyaniline composites have previously been synthesized in a ore-shellstructure but the new method provides an internal void within the polymer shell called a olk-shellstructure. hen the lithium-sulfur battery was discharged fully the volume of the sulfur expanded dramatically to 200 percent.
If you think about the beauty of an egg yolk there is some empty space inside with space for the yolk to expandyu says.
#Ceramic converter tackles solar cell problem Stanford university rightoriginal Studyposted by Mark Shwartz-Stanford on October 21 2013coating a solar cell component in ceramics makes it more heat resistant
When subjected to temperatures of 1800 F (1000 C) the ceramic-coated emitters retained their structural integrity for more than 12 hours.
The ceramic-coated emitters were sent to Fan and his colleagues at Stanford who confirmed that devices were still capable of producing infrared light waves that are ideal for running solar cells. hese results are unprecedentedsays former Illinois graduate student Kevin Arpin the lead author of the study. e demonstrated for the first time that ceramics
could help advance thermophotovoltaics as well other areas of research including energy harvesting from waste heat high-temperature catalysis
is established well. opefully these results will motivate the thermophotovoltaics community to take another look at ceramics
#Nanoribbon material keeps gases captive Rice university rightoriginal Studyposted by Mike Williams-Rice on October 11 2013an enhanced polymer could make vehicles that run on compressed natural gas more practical and even prolong the shelf life of bottled beer
and far lighter than the metal in tanks now used to contain the gas say researchers.
By adding modified single-atom-thick graphene nanoribbons (GNRS) to thermoplastic polyurethane (TPU) the team at Rice made it 1000 times harder for gas molecules to escape Tour says.
The researchers led by Rice graduate student Changsheng Xiang produced thin films of the composite material by solution casting GNRS treated with hexadecane and TPU a block copolymer of polyurethane that combines hard and soft materials.
The GNRS geometry makes them far better than graphene sheets for processing into composites Tour says.
Stress and strain tests also found that the 0. 5 percent ratio was optimal for enhancing the polymer s strength. he idea is to increase the toughness of the tank
but a glass bottle until they figured out how to modify plastic to contain the carbon dioxide bubbles.
and in some ways it s the reverse problemhe says. xygen molecules get in through plastic and make the beer go bad.
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