David Kirkpatrick

June 8, 2010

Manufacturing graphene …

Filed under: Science, Technology — Tags: , , , , — David Kirkpatrick @ 3:41 pm

… just got a little bit easier. This is good news out of Rice University. I written this many times, but there’s simply too much smoke in the graphene hype for there not to be a serious fire somewhere. I’m guessing some combination of display technology for handheld electronics is one of the best areas to monitor for market-ready graphene applications.

From the link:

Single-atom-thick sheets of carbon called graphene have some amazing properties: graphene is strong, highly electrically conductive, flexible, and transparent. This makes it a promising material to make flexible touch screens and superstrong structural materials. But creating these thin carbon sheets, and then building things out of them, is difficult to do outside the lab.

Now an advance in making and processing graphene in solution may make it practical to work with the material at manufacturing scale. Researchers at Rice University have made graphene solutions 10 times more concentrated than any before. They’ve used these solutions to make transparent, conductive sheets similar to the electrodes on displays, and they’re currently developing methods for spinning the graphene solutions to generate fibers and structural materials for airplanes and other vehicles that promise to be less expensive than today’s carbon fiber.

Making material: Sheets of graphene lay atop a mat of single-walled carbon nanotubes.
Credit: N. Behabtu/Rice University

June 18, 2009

Cheaper OLEDs

I haven’t had an opportunity to blog about OLEDs in a while, but this looks like a real cost breakthrough. OLEDs have the potential to revolutionize lighting and display technology.

From the link:

Organic light-emitting diodes (OLEDs) are steadily making their way into commercial devices like cell phones and flat-screen displays. They’re fabricated with layers of organic polymers, which make them flexible, and they use less power and less expensive materials than liquid crystal displays.

The downside is that because the polymers react easily with oxygen and water, OLEDs are expensive to produce–they have to be created in high-vacuum chambers–and they need extra protective packaging layers to make sure that once they’re integrated into display devices, they don’t degrade when exposed to air or moisture.

MIT chemical-engineering professor Karen Gleason and MIT postdoc Sreeram Vaddiraju have developed a process that aims to solve the problems of high fabrication costs and instability for OLEDs while still maintaining their flexibility. Gleason’s solution is a hybrid light-emitting diode, or HLED. The device would incorporate both organic and inorganic layers, combining the flexibility of an OLED with the stability of an inorganic light-emitting material. “The idea is to have a mixed bag and capture the qualities that allow inexpensive fabrication and stability,” Gleason says.