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Graphene Is The Strongest Material In The World Even When It Has Defects, Research Finds

Graphene Is The Strongest Material In The World Even When It Has Defects, Research Finds
Clean Power Published on June 2nd, 2013 | by James Ayre June 2nd, 2013 by James Ayre Graphene is the strongest material in the world, even when it has notable defects, new research has found. Image Credit: Illustration by Andrew Shea for Columbia Engineering It’s been said that graphene is so strong that “it would take an elephant, balanced on a pencil, to break through a sheet of graphene the thickness of Saran Wrap.” Graphene is — essentially — just a single atomic layer of carbon that is structured as a honeycomb lattice. The new research corrects the mistaken belief that defects present in graphene are the cause of the extremely low strength seen in some previous studies — the lowered strength is actually the result of the methods used for post-processing CVD-grown graphene. “We substituted a different etchant and were able to create test samples without harming the graphene,” states the paper’s lead author, Gwan-Hyoung Lee, a postdoctoral fellow in the Hone lab. About the Author Related:  nittanyjonesMaterial ScienceMaterials Science

Nanowires grown on graphene have surprising structure (Phys.org) —When a team of University of Illinois engineers set out to grow nanowires of a compound semiconductor on top of a sheet of graphene, they did not expect to discover a new paradigm of epitaxy. The self-assembled wires have a core of one composition and an outer layer of another, a desired trait for many advanced electronics applications. Led by professor Xiuling Li, in collaboration with professors Eric Pop and Joseph Lyding, all professors of electrical and computer engineering, the team published its findings in the journal Nano Letters. Nanowires, tiny strings of semiconductor material, have great potential for applications in transistors, solar cells, lasers, sensors and more. "Nanowires are really the major building blocks of future nano-devices," said postdoctoral researcher Parsian Mohseni, first author of the study. Li's group uses a method called van der Waals epitaxy to grow nanowires from the bottom up on a flat substrate of semiconductor materials, such as silicon.

Impact of Nanotechnology Scientists transform cement into liquid metal It's not the same as turning lead into gold, but scientists at the Illinois-based Argonne National Laboratory and the Japan Synchrotron Radiation Research Institute/SPring-8 have developed a method for turning cement into a liquid metal semiconductor. The process sounds like a mad scientist's invention. It involves equipment like an aerodynamic levitator and a carbon dioxide laser beam. The levitator uses gas pressure to keep the material out of contact with any container surfaces. The carbon dioxide laser beam can heat the material to 3,632 degrees Fahrenheit. The material in question is mayenite, a calcium aluminum oxide material that is part of alimuna cement. "This new material has lots of applications, including as thin-film resistors used in liquid-crystal displays, basically the flat panel computer monitor that you are probably reading this from at the moment," Argonne physicist Chris Benmore said Monday in a statement. Score one for modern alchemy.

Liquid metal brings shape-shifting robot a step closer - tech - 10 March 2015 Video: Self-fuelled liquid metal motor Hasta la vista, baby. A real-life T-1000, the shape-shifting liquid-metal robot from Terminator 2, is a step closer, thanks to a self-powered liquid metal motor. The device is surprisingly simple: just a drop of metal alloy made mostly of gallium – which is liquid at just under 30 °C – with some indium and tin mixed in. When placed in a solution of sodium hydroxide, or even brine, and kept in contact with a flake of aluminium for "fuel", it moves around for about an hour. "The soft machine looks rather intelligent and [can] deform itself according to the space it voyages in, just like [the] Terminator does from the science-fiction film," says Jing Liu from Tsinghua University in Beijing, China. When they first saw the drop move, Liu and colleagues weren't sure how it was able to do so. Other researchers have shown that a stationary gallium drop can act as a pump when in an electric field. More From New Scientist ISIS is waging war on history.

'Soft' approach leads to revolutionary energy storage: Graphene-based supercapacitors Monash University researchers have brought next generation energy storage closer with an engineering first -- a graphene-based device that is compact, yet lasts as long as a conventional battery. Published today in Science, a research team led by Professor Dan Li of the Department of Materials Engineering has developed a completely new strategy to engineer graphene-based supercapacitors (SC), making them viable for widespread use in renewable energy storage, portable electronics and electric vehicles. SCs are generally made of highly porous carbon impregnated with a liquid electrolyte to transport the electrical charge. Known for their almost indefinite lifespan and the ability to re-charge in seconds, the drawback of existing SCs is their low energy-storage-to-volume ratio -- known as energy density. Low energy density of five to eight Watt-hours per litre, means SCs are unfeasibly large or must be re-charged frequently.

Have you ever seen a snowflake grow? Researchers spin a yarn into a muscle An unusually simple approach to artificial muscles – based on high-strength polymer fibres – has been developed by an international team of researchers. Rather than needing sophisticated or expensive materials, the muscles can be produced from simple polymers that are used to make fishing-line or sewing threads. When heated, these fibres can shorten or lengthen far more than biological muscle, and could be used for applications as diverse as temperature-sensitive window shutters, "smart" clothing and robotics. Synthetic sinew Materials that expand and contract in response to some form of stimulus are useful for robotics, where they are used to make "actuators" or artificial muscle fibres, and on smaller scales where they can produce sensors for lab-on-a-chip devices. In the new research, Ray Baughman and colleagues at the University of Texas at Dallas, together with collaborators in Canada, South Korea, Turkey, China and New South Wales in Australia, took a simpler tack. Twisted tendons

Scientists discover whole new state of matter Most people are familiar with some of the common states of matter: solids, liquids and gases. Scientists also recognize a fourth state of matter — plasma — that is commonly observable here on Earth, as well as a host of other states that can only be created in the lab, such as Bose–Einstein condensates and neutron-degenerate matter. Jahn-Teller metals can now be added to this list, a state which appears to have the properties of an insulator, superconductor, metal and magnet all wrapped into one. It's the material's superconductivity which might be the most interesting trait, however. It has the potential to achieve superconductivity at a relatively high critical temperature ("high" as in -135 degrees Celsius as opposed to the sub -243.2 degrees Celsius required by many ordinary metallic superconductors), which is significant for the science of superconductivity. Related on MNN:

New form of carbon said to be strongest material ever found The strongest known material in the world may have just been dethroned. Researchers from Rice University have calculated the properties of a little-studied form of carbon known as carbyne, and they've determined that it should have a "specific strength surpassing that of any other known material." That includes graphene — the longstanding titleholder for strongest material — which the researchers say is only half as stiff as carbyne. Carbyne and graphene are actually alike in several ways: both come from carbon, and both are only a single atom thick. Carbyne has previously been detected in interstellar dust and meteorites.

beesleyII Graphene Gives You Infrared Vision in a Contact Lens It sounds like something from a spy thriller movie: putting on a contact lens that gives you infrared vision without the need for a bulky contraption that covers your face. But now, thanks to research at the University of Michigan, such a contact lens is a real possibility. The Michigan researchers turned to the optical capabilities of graphene to create their infrared contact lens. IBM last year demonstrated some of the photoconductivity mechanisms of graphene that make it an attractive infrared detector. Graphene is capable of detecting the entire infrared spectrum, with visible and ultraviolet light thrown in. "The challenge for the current generation of graphene-based detectors is that their sensitivity is typically very poor," said Zhaohui Zhong, assistant professor at the University of Michigan, in a press release. To achieve this amplification, the researchers started by sandwiching an insulator between two sheets of graphene.

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