Posts belonging to Category electronics

Ultrathin Electronics At Nano Scale

Semiconductors, metals and insulators must be integrated to make the transistors that are the electronic building blocks of your smartphone, computer and other microchip-enabled devices. Today’s transistors are miniscule—a mere 10 nanometers wide—and formed from three-dimensional (3D) crystals.

But a disruptive new technology looms that uses two-dimensional (2D) crystals, just 1 nanometer thick, to enable ultrathin electronics. Scientists worldwide are investigating 2D crystals made from common layered materials to constrain electron transport within just two dimensions. Researchers had previously found ways to lithographically pattern single layers of carbon atoms called graphene into ribbon-like “wires” complete with insulation provided by a similar layer of boron nitride. But until now they have lacked synthesis and processing methods to lithographically pattern junctions between two different semiconductors within a single nanometer-thick layer to form transistors, the building blocks of ultrathin electronic devices. Now for the first time, researchers at the Department of Energy’s Oak Ridge National Laboratory (ONRL) have combined a novel synthesis process with commercial electron-beam lithography techniques to produce arrays of semiconductor junctions in arbitrary patterns within a single, nanometer-thick semiconductor crystal.

scalable arrays of semiconductor junctions

We can literally make any kind of pattern that we want,” said Masoud Mahjouri-Samani, who co-led the study with David Geohegan. Geohegan, head of ORNL’s Nanomaterials Synthesis and Functional Assembly Group at the Center for Nanophase Materials Sciences, is the principal investigator of a Department of Energy basic science project focusing on the growth mechanisms and controlled synthesis of nanomaterials.
Millions of 2D building blocks with numerous patterns may be made concurrently, Mahjouri-Samani added. In the future, it might be possible to produce different patterns on the top and bottom of a sheet.


Yarns that store and release electrical power

Wearable electronic devices for health and fitness monitoring are a rapidly growing area of consumer electronics; one of their biggest limitations is the capacity of their tiny batteries to deliver enough power to transmit data. Now, researchers at MIT and in Canada have found a promising new approach to delivering the short but intense bursts of power needed by such small devices. The key is a new approach to making supercapacitors — devices that can store and release electrical power in such bursts, which are needed for brief transmissions of data from wearable devices such as heart-rate monitors, computers, or smartphones, the researchers say. They may also be useful for other applications where high power is needed in small volumes, such as autonomous microrobots.

The new approach uses yarns, made from nanowires of the element niobium, as the electrodes in tiny supercapacitors (which are essentially pairs of electrically conducting fibers with an insulator between). The concept is described in a paper in the journal ACS Applied Materials and Interfaces by MIT professor of mechanical engineering Ian W. Hunter, doctoral student Seyed M. Mirvakili, and three others at the University of British Columbia.

Nanotechnology researchers have been working to increase the performance of supercapacitors for the past decade. Among nanomaterials, carbon-based nanoparticles — such as carbon nanotubes and graphene — have shown promising results, but they suffer from relatively low electrical conductivity, Mirvakili says.

In this new work, he and his colleagues have shown that desirable characteristics for such devices, such as high power density, are not unique to carbon-based nanoparticles, and that niobium nanowire yarn is a promising an alternative.

MIT-Nanowires-1Yarn made of niobium nanowires, seen here in a scanning electron microscope image (background), can be used to make very efficient supercapacitors, MIT researchers have found. Adding a coating of a conductive polymer to the yarn (shown in pink, inset) further increases the capacitor’s charge capacity. Positive and negative ions in the material are depicted as blue and red spheres.

Imagine you’ve got some kind of wearable health-monitoring system,” Hunter says, “and it needs to broadcast data, for example using Wi-Fi, over a long distance.” At the moment, the coin-sized batteries used in many small electronic devices have very limited ability to deliver a lot of power at once, which is what such data transmissions need.

Long-distance Wi-Fi requires a fair amount of power,” says Hunter, the George N. Hatsopoulos Professor in Thermodynamics in MIT’s Department of Mechanical Engineering, “but it may not be needed for very long.” Small batteries are generally poorly suited for such power needs, he adds.

We know it’s a problem experienced by a number of companies in the health-monitoring or exercise-monitoring space. So an alternative is to go to a combination of a battery and a capacitor,” Hunter says: the battery for long-term, low-power functions, and the capacitor for short bursts of high power. Such a combination should be able to either increase the range of the device, or — perhaps more important in the marketplace — to significantly reduce size requirements.


Electric Planes Cross The Channel

Airbus Group  Friday completed its first-ever flight of an electric plane across the English Channel as the European plane maker seeks to spark interest in less polluting aircraft.

E fan

Airbus’s two-seat E-Fan demonstrator plane powered exclusively by lithium-batteries took 36 minutes to fly from Lydd in southern England to Calais, France, on the historic hop. It came soon after the single-seat Solar Impulse 2 flew from Japan to Hawaii in the longest-ever solar-powered flight as part of an around-the-world journey.

Just as cars are moving from burning fossil fuels to battery power, aircraft makers are exploring a similar shift to reduce carbon dioxide emissions. “It’s a big steppingstone,” said Jean Botti, chief technical officer at Airbus.

Private pilot Hugues Duval beat Airbus to the bragging rights of completing the first-ever Channel crossing in an electric plane when he traversed the body of water on Thursday in his single-seat Cri-Cri plane.

Airbus, better known for making airliners seating more than 100 passengers, plans to start delivering two-seat production versions of the E-Fan in 2017 through its VoltAir subsidiary.

A four-seat E-Fan 4.0 could follow 18 months later. It would introduce hybrid technology that could provide a springboard to building regional planes carrying 100 passengers, Mr. Botti said.



Graphene Doubles Battery Life Of Your Phone

A team of researches affiliated with Samsung’s Advanced Institute of Technology, along with colleagues from other institutions in Korea has found a way to greatly extend lithium-ion battery life.

Consumers want their phone batteries to last longer—that is no secret, and battery life has been extended, but mostly due to improved efficiency of the electronics that depend on it. Researchers at and elsewhere have been working hard to find a way to get more power out of the same size battery but have to date, not made much progress. In this new effort, the researchers looked to silicon and graphene for a better battery.

The team started by using silicon as the material for their anode, rather than the traditional graphite—it is denser and therefore can hold more charge—and is something other researchers have tried before. The problem has always been that in order to charge it, lithium must be added, which causes the anode to expand, a deal breaker for small electronic devices. To circumvent that problem, the researches grew carbide-free graphene (to keep it from forming they developed a process which included using a mild oxidant) on its surface creating a protective and restrictive coating. In addition to preventing expansion, the graphene also helped prevent the silicon from breaking down over time (which occurs due to constant expanding and contracting).

Testing showed that the arrangement resulted in a battery that had an initial energy density that was 1.8 times that of conventional batteries, and held steady at 1.5 times after repeated use. Translated to the real world that would mean a battery that at least initially, would last nearly twice as long as conventional batteries.

In their paper published in the journal Nature Communications, the team describes their new technique and the results they achieved using it.


Electric Car: Water Is The Future Fuel

Canadelectrochim, a non profit research and development Canadian company, have discovered a new non-platinum and nano-sized catalyst for the fuel cell based on Mother Nature which mimics the plant leaf.  The Polymer electrolyte membrane or proton exchange membrane fuel cell (PEMFC) as an optimal solution for the future energy economy.
hydrogen fuel cellsThe PEMFC, where chemical energy is directly converted to electrical energy, provides a highly efficient alternative to a standard internal combustion engine. High power density, clean emissions (water), low temperature operation, rapid start-up and shutdown, and ability to use fuels from renewable sources are several reason why fuel cells such as PEMFC have attracted attention for large market applications, such as transportation. With these unique features, PEMFC will revolutionize the future energy economy.
PEMFC will indirectly make water our future fuel. Hydrogen and oxygen generated by splitting water using photosynthesis can be used as a fuel for PEMFC. PEMFC are leading candidates to power the space shuttle and other mobile applications even down to mobile phones, however, there are still some important issues that must be resolved in order for PEMFC to be commercially competitive. It is known that splitting a hydrogen molecule at the anode of fuel cell using platinum is relatively easy. Unfortunately however, splitting the oxygen molecule at the cathode of fuel cell (oxygen reduction reaction (, ORR)) is more difficult and this causes significant polarization losses (lowers efficiency of the fuel cell). An appropriate catalyst for this process has not been discovered and as of yet platinum is the best option. In the direction of operating the fuel cell using a cost effective and non-platinum based catalyst, is the work of Canadelectrochim.


Fly With Your Own Jetpack

It’s the world’s first commercial jetpack and could be yours for 150,000 USD. Three decades of research has gone into the Martin Jetpack, which in tests flew at more than 1,000 metres above ground, at up to 74 miles per hour (120 km/h). This simulator gave Paris Airshow visitors a taste of what flying a real jetpack might feel like.


It actually flies the same as the jetpack, so it’s an opportunity for members of the public to see what that experience is all about,” said Peter Coker, chief executive of the New Zealand based company Martin Jetpack. The jetpack is totally safe: “We have safety built into the actual structure itself. Very similar to a Formula One racing car, and finally what we actually have is a new ballistic parachute that is the basis of recognising the way that we can be as safe as we possibly can. It opens at very low altitude and actually saves both the aircraft and the pilot in an emergency“.

The newest, P12 version, runs on a petrol engine that drives two ducted fans and can carry a commercial payload of 120 kilograms. Although it will interest rich thrill-seekers, it’s aimed primarily at emergency responders in hard to reach areas, and search and rescue missions. Vertical Take-off and Landing means the P12 can land on rooftops covered with aerials and wires, and fly into tightly confined areas. It can stay in the air for 30 minutes and the firm calls it a practical alternative to helicopters. Chinese aerospace group Kuang-Chi Science has committed 40 million dollars of funding. Chairman Dr Ruopeng Liu is keen to try one for himself. “For sure, I would fly it by myself and I will even buy one for myself. It’s one of the finest machines I’ve ever seen in the world and people will love it,” says Dr Ruopeng Liu. First deliveries of the jetpack are scheduled for late 2016. Its makers are sure that sales will soar.



Printing With Nanomaterials

Researchers at Binghamton University are focusing on printed electronics: using inkjet technology to print electronic nanomaterials onto flexible substrates. When compared to traditional methods used in microelectronics fabrication, the new technology conserves material and is more environmentally friendly.

Think of inkjet printing and you’ll likely picture an old printer in an office. Not so if you’re Timothy Singler, director of graduate studies and professor of mechanical engineering at Binghamton University. In the Transport Sciences Core at the Innovative Technologies Complex, Singler is collaborating with Paul Chiarot and Frank Yong, assistant professors of mechanical engineering, to study inkjet printing of functional materials.

Functional materials are categorized in terms of the actions they can perform rather than on the basis of their origins. Solution-processed materials may have electrical, optical, chemical, magnetic, thermal or other functionalities. For example, silver is strongly electrically conductive and can be formulated into nanoparticle ink. However, Singler explains that printing with solution-processed nanomaterials instead of traditional inks is significantly more complex.

3D printing “One really has to study how nanomaterials deposit on a substrate — what structures they form, how you can control them — because you’re dispersing the nanomaterials into a liquid so you can print them, and that liquid volatilizes, leaving only the material on the substrate. But the evaporation process and capillarity cause very complex flows that transport the material you’re trying to deposit in nonintuitive ways,” Singler says. “These flows have to be controlled to achieve an optimal functional structure at the end.”


Perfect Artificial Skin For Robots

A pioneering new technique to produce high-quality, low cost graphene could pave the way for the development of the first truly flexibleelectronic skin’, that could be used in robots.

Researchers from the University of Exeter (UK) have discovered an innovative new method to produce the wonder material Graphene significantly cheaper, and easier, than previously possible.

The research team, led by Professor Monica Craciun, have used this new technique to create the first transparent and flexible touch-sensor that could enable the development of artificial skin for use in robot manufacturing. Professor Craciun, from Exeter’s Engineering department, believes the new discovery could pave the way for “a graphene-driven industrial revolution” to take place.

robot female

The vision for a ‘graphene-driven industrial revolution’ is motivating intensive research on the synthesis of high quality and low cost graphene. Currently, industrial graphene is produced using a technique called Chemical Vapour Deposition (CVD). Although there have been significant advances in recent years in this technique, it is still an expensive and time consuming process, ”she said.

The Exeter researchers have now discovered a new technique, which grows graphene in an industrial cold wall CVD system, a state-of-the-art piece of equipment recently developed by UK graphene company Moorfield.

This so-called nanoCVD system is based on a concept already used for other manufacturing purposes in the semiconductor industry. This shows to the semiconductor industry for the very first time a way to potentially mass produce graphene with present facilities rather than requiring them to build new manufacturing plants. This new technique grows graphene 100 times faster than conventional methods, reduces costs by 99 % and has enhanced electronic quality.

These research findings are published in the journal Advanced Materials.


Full-Color, Flexible, Skin-like Display

Imagine a soldier who can change the color and pattern of his camouflage uniform from woodland green to desert tan at will. Or an office worker who could do the same with his necktie. Is someone at the wedding reception wearing the same dress as you? No problem – switch yours to a different color in the blink of an eye.

A breakthrough in a University of Central Florida (UCF) lab has brought those scenarios closer to reality. A team led by Professor Debashis Chanda of UCF’s NanoScience Technology Center and the College of Optics and Photonics (CREOL) has developed a technique for creating the world’s first full-color, flexible thin-film reflective display.

Chanda’s research was inspired by nature. Traditional displays like those FLEXIon a mobile phone require a light source, filters and a glass plates. But animals like chameleons, octopuses and squids are born with thin, flexible, color-changing displays that don’t need a light source – their skin.


All manmade displays – LCD, LED, CRT – are rigid, brittle and bulky. But you look at an octopus, they can create color on the skin itself covering a complex body contour, and it’s stretchable and flexible,” Chanda said. “That was the motivation: Can we take some inspiration from biology and create a skin-like display?”

As detailed in the cover article of the June issue of the journal Nature Communications, Chanda is able to change the color on an ultrathin nanostructured surface by applying voltage. The new method doesn’t need its own light source. Rather, it reflects the ambient light around it.


Wood Added With Carbon Nanotubes Printed In 3D

Paul Gatenholm, professor in Polymer TA group of researchers at Chalmers University of Technology (Sweden)  have managed to print and dry three-dimensional objects made entirely by cellulose for the first time with the help of a 3D-bioprinter. They also added carbon nanotubes to create electrically conductive material. The effect is that cellulose and other raw material based on wood will be able to compete with fossil-based plastics and metals in the on-going additive manufacturing revolution, which started with the introduction of the 3D-printer.

3D printing is a form of additive manufacturing that is predicted to revolutionise the manufacturing industry. The precision of the technology makes it possible to manufacture a whole new range of objects and it presents several advantages compared to older production techniques. The freedom of design is great, the lead time is short, and no material goes to wastePlastics and metals dominate additive manufacturing. However, a research group at Chalmers University of Technology have now managed to use cellulose from wood in a 3D printer.

wood computer chipCombing the use of cellulose to the fast technological development of 3D printing offers great environmental advantages,” says Paul Gatenholm, professor of Biopolymer Technology at Chalmers and the leader of the research group. “Cellulose is an unlimited renewable commodity that is completely biodegradable, and manufacture using raw material from wood, in essence, means to bind carbon dioxide that would otherwise end up in the atmosphere.”

The breakthrough was accomplished at Wallenberg Wood Science Center, a research center aimed at developing new materials from wood, at Chalmers University of Technology.