The Year in Materials
Wonder material graphene wins Nobel Prize, flexible electronics head to market, and advances hint at the future of displays.
Graphene is a material of many superlatives. Notably, it’s the best conductor of electricity at room temperature and the strongest material ever tested. Now, just six years after their groundbreaking work, the two who performed the first experiments on the single-atom-thick carbon material (Graphene Wins Nobel Prize), Andre Geim and Konstantin Novoselov, both in the physics department at the University of Manchester, have received the 2010 Nobel Prize in Physics.
Perhaps one reason the prize was bestowed so soon after the work it recognizes is that materials scientists have already taken graphene from basic science experiments to prototypes of new devices. In one noteworthy example from this year, researchers at IBM made graphene transistor arrays that operate at 100 gigahertz—switching on and off 100 billion times each second, about 10 times as fast as the speediest silicon transistors (Graphene Transistors that Can Work at Blistering Speeds). Work at Samsung capitalized on graphene’s conductivity and flexibility to make flexible touch screens (Flexible Touch Screen Made with Printed Graphene).
Flexible Printed Electronics Advance
Other flexible materials for electronics also saw progress this year. Working with carbon nanotubes, researchers at Northwestern University and the University of Minnesota made the fastest printed electronics yet (Record Performance for Printed Electronics). Printed electronics holds out the promise of flexible devices that can be fabricated at high volume and low cost. Researchers at HP continued their work scaling up flexible display drivers made from thin films of silicon on rolls of plastic (Inexpensive, Unbreakable Displays and A Flexible Color Display). Meanwhile, groups at Stanford and the University of California, Berkeley, printed pressure sensors that match the sensitivity of human skin (Electric Skin that Rivals the Real Thing and Printing Electronic Skin).
And a startup in Cambridge, Massachusetts, took steps this year toward commercializing high-performance printed electronics. MC10 announced collaborations with Reebok and Diagnostics for All aimed at getting its stretchable arrays of integrated circuits, LEDs, and other silicon devices into products (Stretchable Silicon Could Make Sports Apparel Smarter and Cheap Electronics on Paper Diagnostic Chips).
MC10’s silicon-printing method, originally developed by John Rogers at the University of Illinois, works with a variety of substrates, including silk. Silicon-silk electronics—a facet of one of our Ten Emerging Technologies of 2010—should make possible smarter, more biocompatible medical implants (TR10: Implantable Electronics and Brain Interfaces Made of Silk). The implantable-electronics work uses silkworm silk as a tissue-friendly substrate. Spider silk is lightweight and tougher than steel, but materials scientists haven’t been able to get it in large enough quantities to realize its potential for industrial applications. Two 2010 advances in making transgenic silk-producing creatures, E. coli and silkworms, might change that (Making Spider Strength Materials and Transgenic Worms Make Tough Fibers).
Displays of the Future
While gadget hounds delighted in the new iPad, materials-science geeks lamented the continuing dominance of power-hungry liquid-crystal displays that useheavy pieces of glass. A lightweight wrist-mounted display prototyped for the U.S. Army employed new, more efficient organic light-emitting diodes (Thin Displays as Wristbands). And two companies making quantum dots partnered with display manufacturer LG to improve the efficiency of LCD backlights (Colorful Quantum-Dot Displays Coming to Market) and to make a new type of display, a quantum-dot light-emitting diode (Quantum Dot Displays Start to Shine).
New materials also pushed displays beyond conventional eye-strain-inducing 3-D that requires viewers to wear special glasses. Researchers at the University of Arizona and Nitto Denko Technical used a blend of electrically responsive light-scattering polymers to make a holographic videoconferencing system (A Step toward Holographic Videoconferencing). The holographic display refreshes every two seconds; with further improvements, it will attain video rates.
Rare Earths on the Radar
The year found many twisting their mouths around names like praseodymium and neodymium for the first time as the lanthanoid row of the periodic table came into the news. Many high-tech and clean-tech devices, such as lightweight permanent magnets for computer hard drives and wind turbines, require rare-earth metals, and demand for them is growing. China currently supplies 95 percent of the world’s rare earths, and some worry about future supplies of these critical raw materials. Companies including GE and Hitachi are working on alternative technologies that require smaller quantities of rare-earth elements or none at all (China’s Rare-Earth Monopoly). Meanwhile, the U.S. company Molycorp and the Australian company Lynas detailed plans for rare-earth mining operations in Mountain Pass, California, and Perth (Can the U.S. Rare-Earth Industry Rebound?).