[Home]
[Full version]
Graphene-based gadgets may be just years away
Apr 30 ,Nanotechnology
Researchers at The University of Manchester have produced tiny liquid crystal devices with electrodes made from graphene – an exciting development that could lead to computer and TV displays based on this technology.
Writing in the American Chemical Society’s journal Nano Letters, Dr Kostya Novoselov and colleagues from The School of Physics and Astronomy and The School of Computer Science, report on the use of graphene as a transparent conductive coating for electro-optical devices – and show that its high transparency and low resistivity make it ideal for electrodes in liquid crystal devices.
Graphene was discovered at The University of Manchester back in 2004, by Professor Andre Geim FRS and Royal Society Research Fellow Dr Kostya Novoselov. This incredible one-atom-thick gauze of carbon atoms, which resembles chicken wire, has quickly become one of the hottest topics in physics and materials science.
“Graphene is only one atom thick, optically transparent, chemically inert, and an excellent conductor,” says Dr Novoselov, from the Manchester research team.
“These properties seem to make this material an excellent candidate for applications in various electro-optical devices that require conducting but transparent thin films. We believe graphene should improve the durability and simplify the technology of potential electronic devices that interact with light.”
Prof Geim said: “Transparent conducting films are an essential part of many gadgets including common liquid crystal displays (LCDs) for computers, TVs and mobile phones.
“The underlying technology uses thin metal-oxide films based on indium. But indium is becoming an increasingly expensive commodity and, moreover, its supply is expected to be exhausted within just 10 years.
“Forget about oil – our civilisation will first run out of indium. Scientists have an urgent task on their hands to find new types of conductive transparent films.”
The Manchester research team has now demonstrated highly transparent and highly conductive ultra-thin films that can be produced cheaply by ‘dissolving’ chunks of graphite – an abundant natural resource – into graphene and then spraying the suspension onto a glass surface.
The resulting graphene-based films can be used in LCDs and, to prove the concept, the research team have demonstrated the first liquid crystal devices with graphene electrodes.
Dr Novoselov believes that there are only a few small, incremental steps remain for this technology to reach a mass production stage. “Graphene-based LCD products could appear in shops as soon as in a few years”, he adds.
A research team from the Max Planck Institute for Polymer Research in Germany recently reported in Nano Letters how they had used graphene-based films to create transparent electrodes for solar cells [Wang, X.; Zhi, L.; Mullen, K. Nano Lett. 2008, 8, 323.].
But the German team used a different technology for obtaining graphene films, which involved several extra steps.
The Manchester team says the films they have developed are much simpler to produce, and they can be used not only in LCDs but also in solar cells.
Source: University of Manchester
Related stories:
New graphene-based material clarifies graphite oxide chemistry
A new "graphene-based" material that helps solve the structure of graphite oxide and could lead to other potential discoveries of the one-atom thick substance called graphene, which has applications in nanoelectronics, energy storage and production, and transportation such as airplanes and cars has been created by researchers at The University of Texas at Austin.
Scientists demonstrate potential of graphene films as next-generation transistors
Physicists at the University of Pennsylvania have characterized an aspect of graphene film behavior by measuring the way it conducts electricity on a substrate. This milestone advances the potential application of graphene, the ultra-thin, single-atom thick carbon sheets that conduct electricity faster and more efficiently than silicon, the current material of choice for transistor fabrication.
Engineers Prove Graphene is the Strongest Material
(PhysOrg.com) -- Research scientists at Columbia University’s Fu Foundation School of Engineering and Applied Science have achieved a breakthrough by proving that the carbon material graphene is the strongest material ever measured.
Carbon nanoribbons could make smaller, speedier computer chips
Stanford chemists have developed a new way to make transistors out of carbon nanoribbons. The devices could someday be integrated into high-performance computer chips to increase their speed and generate less heat, which can damage today's silicon-based chips when transistors are packed together tightly.
Physicists show electrons can travel over 100 times faster in graphene than in silicon
University of Maryland physicists have shown that in graphene the intrinsic limit to the mobility, a measure of how well a material conducts electricity, is higher than any other known material at room temperature. Graphene, a single-atom-thick sheet of graphite, is a new material which combines aspects of semiconductors and metals.
Graphene oxide paper could spawn a new class of materials
Nearly 2,000 years ago, the discovery of paper revolutionized human communication. Now researchers at Northwestern University have fabricated a new type of paper that they hope will create a revolution of its own -- and while it won't replace your notepad, this remarkably stiff and strong yet lightweight material should find use in a wide variety of applications.
A new type of spin valve that uses graphene
“Some people think that graphene, a form of carbon, is the material of the future,” Allen Goldman tells
PhysOrg.com. “It’s of high scientific interest because of its unusual electronic properties.”
Disorder May Be in Order for ‘Spintronic’ Devices
Physicists at JILA are using ultrashort pulses of laser light to reveal precisely why some electrons, like ballet dancers, hold their spin positions better than others—work that may help improve spintronic devices, which exploit the magnetism or “spin” of electrons in addition to or instead of their charge. One thing spinning electrons like, it turns out, is some disorder.
[Home]
[Full version]