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Researchers Take Carbon To a New Form :Graphene
Researchers Take Carbon To a New Form :Graphene
Researchers at Boston College and Nagoya University have synthesized another form of carbon unofficially dubbed "grossly wraped nanographenes." The research, which was published in the journal Nature Chemistry,has led to creating a material that is essentially defect in two dimensional hexagonal honeycomb of trigonal carbon atoms found in graphene. These defects consist of non-hexagonal rings that force distortions out of the two-dimensional structure.
The grossly warped nanographene consists of 80 carbon atoms joined together in a network of 26 rings, with 30 hydrogen atoms on the outside rim. In contrast to graphene sheets, which typically have planar two-dimensional geometries, the new material juts out from a single plane because of the five 7-membered rings and one 5-membered ring embedded in the hexagonal lattice of carbon atoms.
Pushing its geometry out of planarity has altered the new material's physical, optical, and electronic properties vis-à-vis its carbon cousins.
“Our new grossly warped nanographene is dramatically more soluble than a planar nanographene of comparable size,” said Lawrence T. Scott, professor at Boston College and one of the principal authors of the research, in a press release. “The two differ significantly in color, as well. Electrochemical measurements revealed that the planar and the warped nanographenes are equally easily oxidized, but the warped nanographene is more difficult to reduce.”
These are just the initial differentiating characteristics of this new form of carbon. If the near-decade-long history of graphene is any guide, we can expect new properties to be discovered on a regular basis.
Graphene Optical Switches One Hundred Times Faster Than Current Devices
Researchers at the University of Bath in the U.K. are reporting measurements indicating that graphene could lead to optical switches that are nearly a hundred times faster than materials used in today’s current switches.
The research, which was published in the journal Physical Review Letters(“Carrier Lifetime in Exfoliated Few-Layer Graphene Determined from Intersubband Optical Transitions”), found that the response rate of an optical switch using graphene to be around 100 femtoseconds, which is about a hundred times faster than the few picoseconds measured in today’s devices.
“We’ve seen an ultrafast optical response rate, using few-layer graphene, which has exciting applications for the development of high speed optoelectronic components based on graphene,” said lead researcher Dr. Enrico Da Como in a press release. “This fast response is in the infrared part of the electromagnetic spectrum, where many applications in telecommunications, security, and also medicine are currently developing and affecting our society.”
In addition to photodetectors and optical switches, graphene is proving attractive for tunable notch filters, an area where IBM has made some interesting progress. Also, researchers have been able to exploit graphene’s wide spectral range for different kinds of tunable lasers that are used in optoelectronic systems.
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