Graphene, Not Glass, Is The Key To Better Optics

A lens just a billionth of a metre thick could transform phone cameras. Researchers at Swinburne University in Melbourne, Australia, have created ultra-thin lenses that cap an optical fibre, and can produce images with the quality and sharpness of much larger glass lenses.

Compared with current lenses, our graphene lens only needs one film to achieve the same resolution,” says Professor Baohua Jia, a research leader at Swinburne’s Centre for Micro-Photonics. “In the future, mobile phones could be much thinner, without having to sacrifice the quality of their cameras. Our lens also allows infrared light to pass through, which glass lenses don’t.”

Producing graphene can be costly and challenging, so Baohua and her colleagues used a laser to pattern layers of graphene oxide (graphene combined with oxygen). By then removing the oxygen, they produced low-cost, patterned films of graphene, a thousand times thinner than a human hair. “By patterning the graphene oxide film in this way, its optical and electrical properties can be altered, which allowed us to place them in different devices,” she says.

Warm objects give off infrared light, so mobile phones with graphene lenses could be used to scan for hotspots in the human body and help in the early identification of diseases like breast cancer. By attaching the lens to a fibre optic tip, endoscopes — instruments that are currently several millimetres wide—could be made a million times smaller. The team is also investigating graphene’s amazing properties for their potential use as supercapacitors, capable of storing very large amounts of energy, which could replace conventional batteries.

Baohua’s work on graphene lenses was published in Nature Communications.

Source: https://cosmosmagazine.com/

How To Destroy SuperBugs

A new discovery could control the spread of deadly antibiotic-resistant superbugs which experts fear are on course to kill 10 million people every year by 2050 – more than will die from cancer. A team of scientists, led by Professor Suresh C. Pillai from IT Sligo (Ireland), have made the significant breakthrough which will allow everyday items – from smartphones to door handles — to be protected against deadly bacteria, including MRSA and E. coli. News of the discovery comes just days after UK Chancellor of the Exchequer George Osborne warned that superbugs could become deadlier than cancer and are on course to kill 10 million people globally by 2050.

superbug bacteria

Speaking at the International Monetary Fund (IMF) in Washington, Mr Osborne warned that the problem would slash global GDP by around €100 trillion if it was not tackled. Using nanotechnology, the discovery is an effective and practical antimicrobial solution — an agent that kills microorganisms or inhibits their growth — that can be used to protect a range of everyday items. Items include anything made from glass, metallics and ceramics including computer or tablet screens, smartphones, ATMs, door handles, TVs, handrails, lifts, urinals, toilet seats, fridges, microwaves and ceramic floor or wall tiles. It will be of particular use in hospitals and medical facilities which are losing the battle against the spread of killer superbugs. Other common uses would include in swimming pools and public buildings, on glass in public buses and trains, sneeze guards protecting food in delis and restaurants as well as in clean rooms in the medical sector.

The discovery is the culmination of almost 12 years of research by a team of scientists, led by Prof. Suresh C. Pillai initially at CREST (Centre for Research in Engineering Surface Technology) in Dublin Institute of Technology (DIT) and then at IT Sligo’s Nanotechnology Research Group (PEM Centre).

It’s absolutely wonderful to finally be at this stage. This breakthrough will change the whole fight against superbugs. It can effectvely control the spread of bacteria,” said Prof. Pillai. He continued: “Every single person has a sea of bacteria on their hands. The mobile phone is the most contaminated personal item that we can have. Bacteria grows on the phone and can live there for up to five months. As it is contaminated with proteins from saliva and from the hand, It’s fertile land for bacteria and has been shown to carry 30 times more bacteria than a toilet seat.”

The research started at Dublin Institute of Technology (DIT)’s CREST and involves scientists now based at IT Sligo, Dublin City University (DCU) and the University of Surrey. Major researchers included Dr Joanna Carroll and Dr Nigel S. Leyland.

The research was published today in the journal, Scientific Reports, published by the Nature publishing group.

Source: https://itsligo.ie/

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.


graphene4
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.

Source: http://phys.org/

2016: The End Of Cables, A Completely Wireless PC

Intel‘s Skylake, which is the company’s post-Broadwell next-generation platform, will allow the PC maker to eliminate the need for any cables by 2016. Kirk Skaugen, Intel senior Vice-President , has demonstrated at Taipei’s Computex show wireless capabilities for docking, charging and display, which are the last functions for the PC that still require cables. A completely wireless PC has long been desired, but the idea has faced much difficulty because of the need for connecting cables by PC peripherals, along with the system’s need for power.

Intel is looking to use WiGig, a new protocol that can deliver speeds of up to 7 Gbps, to provide short-range docking for display and connectivity The WiGig instantly connects screens and other peripherals when a tablet or laptop appears within the device’s range, and also instantly disconnects as the tablet or laptop is moved away. Users can project what’s on their computer screen to other computer screens wirelessly.

For power, on the other hand, Intel is looking at using Rezence, which Skaugen demonstrated. Rezence is a charging technology that uses magnetic resonance (The phenomenon of absorption of certain frequencies of radio and microwave radiation by atoms placed in a magnetic field. The pattern of absorption reveals molecular structure). The technology is promoted by Intel-backed group Alliance 4 Wireless Power. It can be placed underneath the surface of a table, with the system’s magnetic resonance able to charge devices through even 2 inches of wood. Also, unlike inductive chargers that can only charge one device at a time, magnetic resonance chargers can charge several devices all at once.

The system was also demonstrated by Skaugen at Computex, using a table installed with Rezence to charge a mobile phone, a headset, a laptop and a tablet simultaneously. Skaugen also announced new member companies of the A4WP, which includes Lenovo, Fujitsu, Dell, Panasonic and Logitech, to work with already partners Toshiba and Asus.

Let’s remind that the company Apple has dabbled into magnetic resonance charging technology in the past, filing a patent for the technology.

Source: http://www.techtimes.com/

Smartphones Printed On T-shirts

A new version of “spaser” technology being investigated could mean that mobile phones become so small, efficient, and flexible they could be printed on clothing.
A team of researchers from Monash University – Australia – Department of Electrical and Computer Systems Engineering (ECSE) has modelled the world’s first spaser (surface plasmon amplification by stimulated emission of radiation) to be made completely of carbon.
A spaser is effectively a nanoscale laser or nanolaser. It emits a beam of light through the vibration of free electrons, rather than the space-consuming electromagnetic wave emission process of a traditional laser.
PhD student and lead researcher Chanaka Rupasinghe said the modelled spaser design using carbon would offer many advantages.

Other spasers designed to date are made of gold or silver nanoparticles and semiconductor quantum dots while our device would be comprised of a graphene resonator and a carbon nanotube gain element,” Chanaka said.
The use of carbon means our spaser would be more robust and flexible, would operate at high temperatures, and be eco-friendly.
Because of these properties, there is the possibility that in the future an extremely thin mobile phone could be printed on clothing.”

Source: http://monash.edu/

What is a Triboelectric Generator?

With one stomp of his foot, Georgia Tech Porfessor Zhong Lin Wang illuminates a thousand LED bulbs – with no batteries or power cord. The current comes from essentially the same source as that tiny spark that jumps from a fingertip to a doorknob when you walk across carpet on a cold, dry day. Wang and his research team have learned to harvest this power and put it to work. Wang is using what’s technically known as the triboelectric effect to create surprising amounts of electric power by rubbing or touching two different materials together. He believes the discovery can provide a new way to power mobile devices such as sensors and smartphones by capturing the otherwise wasted mechanical energy from such sources as walking, the wind blowing, vibration, ocean waves or even cars driving by.

Beyond generating power, the technology could also provide a new type of self-powered sensor, allowing detection of vibrations, motion, water leaks, explosions – or even rain falling. triboelectric-generator-04

Georgia Tech professor Zhong Lin Wang poses with an array of 1,000 LED lights that can be illuminated by power produced by the force of a shoe striking a triboelectric generator placed on the floor

We are able to deliver small amounts of portable power for today’s mobile and sensor applications,” said Wang, a Regents professor in Georgia Tech’s School of Materials Science and Engineering. “This opens up a source of energy by harvesting power from activities of all kinds.”

The research has been reported in journals including ACS Nano, Advanced Materials, Angewandte Chemie, Energy and Environmental Sciences, Nano Energy and Nano Letters.
Source: http://www.news.gatech.edu/

Solar Cells That Produce Electricity 24/7

Solar cells that produce electricity 24/7, not just when the sun is shining. Mobile phones with built-in power cells that recharge in seconds and work for weeks between charges. These are just two of the possibilities raised by a novel supercapacitor design invented by material scientists at Vanderbilt University, located at Nashville, USA. It is the first supercapacitor that is made out of silicon so it can be built into a silicon chip along with the microelectronic circuitry that it powers. In fact, it should be possible to construct these power cells out of the excess silicon that exists in the current generation of solar cells, sensors, mobile phones and a variety of other electromechanical devices, providing a considerable cost savings.
SupercapacitorSilicon chip with porous surface next to the special furnace where it was coated with graphene to create a supercapacitor electrode
The big challenge for this approach is assembling the materials,” said Pint. “Constructing high-performance, functional devices out of nanoscale building blocks with any level of control has proven to be quite challenging, and when it is achieved it is difficult to repeat.” said Cary Pint, assistant professor at Vanderbilt University.
The findings are described in a paper published in the Oct. 22 issue of the journal Scientific Reports.

Source: http://news.vanderbilt.edu

Tiny Flexible Power Units

Scientists have created a powerful micro-supercapacitor, just nanometres thick, that could help electronics companies develop mobile phones and cameras that are smaller, lighter and thinner than ever before. The tiny power supply measures less than half a centimetre across and is made from a flexible material, opening up the possibility for wearable electronics.
A bottleneck in making portable electronic devices like mobile phones even smaller is reducing the size and increasing the flexibility of the power supplies in electronic circuits. Supercapacitors are attractive power supplies because they can store almost as much energy as a battery, with the advantage of high-speed energy discharge. Supercapacitor electrodes are normally made from carbon or conducting polymers, but these can be relatively costly. A team led by Professor Oliver G Schmidt at the Leibniz Institute for Solid State and Materials Research in Dresden (IFW-Dresden) – Germany – examined the use of manganese dioxide as an alternative electrode material, which is more environmentally friendly and less expensive than the standard materials.

bendable mobile phone

Supercapacitors, as a new class of energy device, can store high energy and provide high power, bridging the gap between rechargeable batteries and conventional capacitors. So we thought a micro-supercapacitor would be an important development in the rapid advance of portable consumer electronics, which need small lightweight, flexible micro-scale power sources” said Dr Chenglin Yan, leader of the research group at IFW-Dresden. “The device could be applied to many miniaturised technologies, including implantable medical devices and active radio frequency identification (RFID) tags for self-powered miniaturised devices.” Dr Yan concluded: “The major challenge we had to overcome in developing this technology was to obtain really high energy density on the micro-scale, at a low cost. The inclusion of gold in our micro-supercapacitor makes it more expensive, so we are now looking at replacing gold with cheaper metals, such as manganese, to make the device more practical for the market.
The research is published in the Royal Society of Chemistry journal Energy & Environmental Science.

Source: http://pubs.rsc.org/ AND http://www.eurekalert.org/

Electric NanoGenerator To Harvest Wasted Energy

Scavenging energy in our living environment is a feasible approach for powering micro/nanodevices and mobile electronics due to their small size, lower power consumption, and special working environment. Nanomaterials have shown unique advantages for energy conversion, including solar cells,  The type of energy to be harvested depends on the applications. For mobile, implantable and personal electronics, solar energy may not be the best choice because solar is not vailable in many cases under which the electronic devices will be utilized. Alternatively, mechanical energy, including vibration, air flow, and human physical motion, is available almost everywhere and at all times, which is called random energy with irregular amplitude and frequencies. Nanogenerator (NG) is a technology that has been developed for harvesting this type of energy using well-aligned nanowire (NW) arrays and sophisticated fabrication procedures,

 
Pr. Zhong Lin Wang from Georgia Tech and his team present a simple, cost-effective, robust, and scalable approach for fabricating a nanogenerator that gives an output power strong enough to continuously drive a commercial liquid crystal display

Sourcehttp://www.nanoscience.gatech.edu/zlwang/paper/2010/10_NL_06.pdf

Body heat to create power for your smartphone

Simply by touching a small piece of Power Felt – a promising new thermoelectric device developed by scientists, Corey Hewitt (Ph.D. graduate student)  has converted his body heat into an electrical current. Comprised of tiny carbon nanotubes locked up in flexible plastic fibers and made to feel like fabric, Power Felt uses temperature differences – room temperature versus body temperature, for instance – to create a charge. The research team  is  from Wake Forest University, North Carolina, , Center for Nanotechnology and Molecular Materials..

We waste a lot of energy in the form of heat. For example, recapturing a car’s energy waste could help improve fuel mileage and power the radio, air conditioning or navigation system,” Hewitt says. “Generally thermoelectrics are an underdeveloped technology for harvesting energy, yet there is so much opportunity.

Cost has prevented thermoelectrics from being used more widely in consumer products. Standard thermoelectric devices use a much more efficient compound called bismuth telluride to turn heat into power in products including mobile refrigerators and CPU coolers, but it can cost $1,000 per kilogram. Like silicon, researchers liken its affordability to demand in volume and think someday Power Felt would cost only $1 to add to a cell phone cover.

 

Source: http://news.wfu.edu/2012/02/22/power-felt-gives-a-charge/