A significant discovery by a team of researchers that includes Assistant Professor Zlatan Aksamija and graduate student Arnab Majee of the Electrical and Computer Engineering Department has been covered widely in many scientific news outlets, including Science Daily, Nanowerk News, Chemeurope.com, Nanotechnology Now, Science Newsline, Lab Manager magazine, Controlled Environments, and Iconnect007.com. The team’s discovery was revealed in a paper first published in the peer-reviewed journal Nano Letters ("Bimodal Phonon Scattering in Graphene Grain Boundaries") examining how heat transfer works in graphene, the one-atom thick sheets of carbon. The team found that as grains of the material become more misaligned, the heat transferring properties decline.
According to Nanowerk News, the researchers have solved the long-standing conundrum of how the boundary between grains of graphene affects heat conductivity in thin films of the miracle substance, thus bringing developers a step closer to being able to engineer films at a scale useful for cooling microelectronic devices and hundreds of other nano-tech applications.
As the Nanowerk article explained, “Since its discovery, graphene – a single layer of carbon atoms linked in a chicken-wire pattern – has attracted intense interest for its phenomenal ability to conduct heat and electricity. Virtually every nanotech device could benefit from graphene’s extraordinary ability to dissipate heat and optimize electronic function, says Poya Yasaei, UIC [University of Illinois at Chicago] graduate student in mechanical and industrial engineering and first author on the paper.”
Nanowerk News added that “In a two-year, multidisciplinary investigation the researchers developed a technique to measure heat transfer across a single grain boundary and were surprised to find that it was an order of magnitude – a full 10 times – lower than the theoretically predicted value. They then devised computer models that can explain the surprising observations from the atomic level to the device level.”
The research was conducted in a collaborative effort by researchers at the University of Illinois at Chicago, the University of Massachusetts Amherst, and Boise State University. (July 2015)