Instead of burning up this complex hydrocarbon, let’s make devices from it, says Jeffrey Grossman.
Jeffrey Grossman thinks we’ve been looking at coal all wrong. Instead of just setting it afire, thus ignoring the molecular complexity of this highly varied material, he says, we should be harnessing the real value of that diversity and complex chemistry. Coal could become the basis for solar panels, batteries, or electronic devices, he and his research team say.
As a first demonstration of what they see as a broad range of potential high-tech uses for this traditionally low-tech material, Grossman, doctoral student Brent Keller, and research scientist Nicola Ferralis have succeeded in making a simple electrical heating device that could be used for defrosting car windows or airplane wings, or as part of a biomedical implant. In developing this initial application, they have also for the first time characterized in detail the chemical, electrical, and optical properties of thin films of four different kinds of coal: anthracite, lignite, and two bituminous types. Their findings have just been reported in the journal NanoLetters.
“When you look at coal as a material, and not just as something to burn, the chemistry is extremely rich,” says Grossman, the Morton and Claire Goulder and Family Professor in Environmental Systems in the Department of Materials Science and Engineering (DMSE). The question he wanted to ask is, “Could we leverage the wealth of chemistry in things like coal to make devices that have useful functionality?” The answer, he says, is a resounding yes.
Researchers have switched an intrinsic property of electrons from an excited state to a relaxed state on demand.
Researchers are exploring how to use NDCX-II to process exotic materials, like the silicon-bismuth sample used in a recent microwave-based experiment relevant to quantum computing. By zapping an exotic silicon material developed at Berkeley Lab with the microwaves, they found that they could rapidly change the electron spins from an excited state to a relaxed, ground state by causing the electrons to emit some of their energy in the form of microwave particles known as photons.
A silicon sampled doped with bismuth atoms (left image) that is just 150 nanometers thick is fitted with a superconducting resonator that includes a capacitor (black, in left image; light gray in center image) and an inductive wire (red line in the left image) that is 5 microns in diameter.
A new world of flexible, bendable, even stretchable electronics is emerging from research labs to address a wide range of potentially game-changing uses. The common, rigid printed circuit board is slowly being replaced by a thin ribbon of resilient, high-performance electronics.
Over the last few years, one team of chemists and materials scientists has begun exploring military applications in harsh environments for aircraft, explosive devices and even combatants themselves.
Researchers will provide an update on the latest technologies, as well as future research plans, at the 250thNational Meeting & Exposition of the American Chemical Society (ACS). ACS is the world’s largest scientific society. The meeting takes place here through Thursday.
“Basically, we are using a hybrid technology that mixes traditional electronics with flexible, high-performance electronics and new 3-D printing technologies,” says Benjamin J. Leever, Ph.D., who is at the Air Force Research Laboratory at Wright-Patterson Air Force Base. “In some cases, we incorporate ‘inks,’ which are based on metals, polymers and organic materials, to tie the system together electronically. With our technology, we can take a razor-thin silicon integrated circuit, a few hundred nanometers thick, and place it on a flexible, bendable or even foldable, plastic-like substrate material,” he says.
Ground-breaking research has successfully created the world’s first truly electronic textile, using the wonder material Graphene
An international team of scientists, including Professor Monica Craciun from the University of Exeter, have pioneered a new technique to embed transparent, flexible graphene electrodes into fibres commonly associated with the textile industry.
The discovery could revolutionise the creation of wearable electronic devices, such as clothing containing computers, phones and MP3 players, which are lightweight, durable and easily transportable.
The international collaborative research, which includes experts from the Centre for Graphene Science at the University of Exeter, the Institute for Systems Engineering and Computers, Microsystems and Nanotechnology (INESC-MN) in Lisbon, the Universities of Lisbon and Aveiro in Portugal and the Belgian Textile Research Centre (CenTexBel), is published in the leading scientific journal Scientific Reports.
Professor Craciun, co-author of the research said: “This is a pivotal point in the future of wearable electronic devices. The potential has been there for a number of years, and transparent and flexible electrodes are already widely used in plastics and glass, for example. But this is the first example of a textile electrode being truly embedded in a yarn. The possibilities for its use are endless, including textile GPS systems, to biomedical monitoring, personal security or even communication tools for those who are sensory impaired. The only limits are really within our own imagination.”
At just one atom thick, graphene is the thinnest substance capable of conducting electricity. It is very flexible and is one of the strongest known materials. The race has been on for scientists and engineers to adapt graphene for the use in wearable electronic devices in recent years.
This new research has identified that ‘monolayer graphene’, which has exceptional electrical, mechanical and optical properties, make it a highly attractive proposition as a transparent electrode for applications in wearable electronics. In this work graphene was created by a growth method called chemical vapour deposition (CVD) onto copper foil, using a state-of-the-art nanoCVD system recently developed by Moorfield.
The collaborative team established a technique to transfer graphene from the copper foils to a polypropylene fibre already commonly used in the textile industry.
Dr Helena Alves who led the research team from INESC-MN and the University of Aveiro said: “The concept of wearable technology is emerging, but so far having fully textile-embedded transparent and flexible technology is currently non-existing. Therefore, the development of processes and engineering for the integration of graphene in textiles would give rise to a new universe of commercial applications. “
Dr Ana Neves, Associate Research Fellow in Prof Craciun’s team from Exeter’s Engineering Department and former postdoctoral researcher at INESC added: “We are surrounded by fabrics, the carpet floors in our homes or offices, the seats in our cars, and obviously all our garments and clothing accessories. The incorporation of electronic devices on fabrics would certainly be a game-changer in modern technology.
“All electronic devices need wiring, so the first issue to be address in this strategy is the development of conducting textile fibres while keeping the same aspect, comfort and lightness. The methodology that we have developed to prepare transparent and conductive textile fibres by coating them with graphene will now open way to the integration of electronic devices on these textile fibres.”
Dr Isabel De Schrijver,an expert of smart textiles fromCenTexBel said: “Successful manufacturing of wearable electronics has the potential for a disruptive technology with a wide array of potential new applications. We are very excited about the potential of this breakthrough and look forward to seeing where it can take the electronics industry in the future.”
Professor Saverio Russo, co-author and also from the University of Exeter, added: “This breakthrough will also nurture the birth of novel and transformative research directions benefitting a wide range of sectors ranging from defence to health care. “
Princeton University researchers have developed a new method to increase the brightness, efficiency and clarity of LEDs, which are widely used on smartphones and portable electronics as well as becoming increasingly common in lighting.
Using a new nanoscale structure, the researchers, led by electrical engineering professor Stephen Chou, increased the brightness and efficiency of LEDs made of organic materials (flexible carbon-based sheets) by 57 percent. The researchers also report their method should yield similar improvements in LEDs made in inorganic (silicon-based) materials used most commonly today.
The method also improves the picture clarity of LED displays by 400 percent, compared with conventional approaches. In an article published online August 19 in the journal Advanced Functional Materials, the researchers describe how they accomplished this by inventing a technique that manipulates light on a scale smaller than a single wavelength.
“New nanotechnology can change the rules of the ways we manipulate light,” said Chou, who has been working in the field for 30 years. “We can use this to make devices with unprecedented performance.”
A LED, or light emitting diode, is an electronic device that emits light when electrical current moves through two terminals. LEDs offer several advantages over incandescent or fluorescent lights: they are far more efficient, compact and have a longer lifetime, all of which are important in portable displays.
Current LEDs have design challenges; foremost among them is to reduce the amount of light that gets trapped inside the LED’s structure. Although they are known for their efficiency, only a very small amount of light generated inside an LED actually escapes.
“It is exactly the same reason that lighting installed inside a swimming pool seems dim from outside – because the water traps the light,” said Chou, the Joseph C. Elgin Professor of Engineering. “The solid structure of a LED traps far more light than the pool’s water.”
First Proof of Ferroelectricity in Simplest Amino Acid
The boundary between electronics and biology is blurring with the first detection by researchers at Department of Energy’s Oak Ridge National Laboratory of ferroelectric properties in an amino acid called glycine.
A multi-institutional research team led by Andrei Kholkin of the University of Aveiro, Portugal, used a combination of experiments and modeling to identify and explain the presence of ferroelectricity, a property where materials switch their polarization when an electric field is applied, in the simplest known amino acid — glycine.
“The discovery of ferroelectricity opens new pathways to novel classes of bioelectronic logic and memory devices, where polarization switching is used to record and retrieve information in the form of ferroelectric domains,” said coauthor and senior scientist at ORNL’s Center for Nanophase Materials Sciences (CNMS) Sergei Kalinin.
Although certain biological molecules like glycine are known to be piezoelectric, a phenomenon in which materials respond to pressure by producing electricity, ferroelectricity is relatively rare in the realm of biology. Thus, scientists are still unclear about the potential applications of ferroelectric biomaterials.
“This research helps paves the way toward building memory devices made of molecules that already exist in our bodies,” Kholkin said.
For example, making use of the ability to switch polarization through tiny electric fields may help build nanorobots that can swim through human blood. Kalinin cautions that such nanotechnology is still a long way in the future.