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03.02.2012 Two-Dimensional Glass

Image/Cornell University, Pinshane Huang, David Muller; (inset) W. H. Zachariasen

Researchers have created the world's thinnest pane of glass—and it looks oddly familiar. The glass, made of silicon and oxygen, formed accidentally when the scientists were making graphene, an atom-thick sheet of carbon, on copper-covered quartz. They believe an air leak caused the copper to react with the quartz, which is also made of silicon and oxygen, producing a glass layer with the graphene. The glass is a mere three atoms thick—the minimum thickness of silica glass—which makes it two-dimensional.

Although this is the first time such a thin sheet of freestanding glass has been produced, the image above, taken with an electron microscope, isn't entirely new. Reporting in an upcoming issue of Nano Letters, the team notes that it "strikingly resembles" a diagram drawn by a glass theorist attempting to unravel its structure back in 1932 (inset). In the ghostly microscope image, two silicon atoms bound together with an oxygen atom appear as white dots, with oxygen atoms forming gray connecting lines.

This network of random-sized rings is mirrored in the old black and white sketch. In addition to demonstrating how graphene makes it possible to produce previously unfeasible 2D-materials, ultra-thin glass could be used in semiconductor or graphene transistors. 

Link:  http://news.sciencemag.org/sciencenow/2012/02/scienceshot-two-dimensional-glass.html?ref=hp
Source:  Science
Author:  Katherine McAlpine
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