While the scientific world has already been abuzz with the potential for the material graphene, a team of researchers at University of California, Riverside, in collaboration with researchers in Texas and China, are fueling more talk about their graphene-with-a-twist and its potential to keep electronic devices from overheating.
They’ve shown that isotopically modified graphene has much better thermal properties and potential to manage heat in a wide variety of applications, including electronics and photovoltaic solar cells.
Now, the scientific community may have been chattering away about graphene since its discovery in 2004, but for those of us who can only deduce that it may be related to graphite, the material in those #2 pencils that you only now use to keep score at miniature golf, we’ll take one step back. Graphene is a one-atom-thick, honeycomb structured sheet of carbon atoms, which stacks to form graphite. For a visual on how thin one atom is, 3 million sheets of stacked graphene would only be one millimeter thick.
So how is graphene more exciting than pencil lead? The one-atom-thick material is incredibly strong, can be stretched by twenty percent without damage, and conducts electricity and heat extraordinarily well. All these traits make it quite exciting for potential high-tech applications.
While graphene’s natural electrical and heat conductivity is respectable already, Professor Alexander Balandin and his team took it to the next level. Natural graphene consists of 99 percent 12C (carbon 12) and 1 percent of 13C (carbon 13). By removing just one percent of the carbon 13, the slight modification (called isotopic purification) gives the graphene even higher thermal conductivity without altering its other properties.
Heat removal is increasingly important as electronics become smaller and smaller, and materials like graphene that conduct heat really well are critical to developing the next generation of electronics. According to Balandin, this isotopically pure graphene could begin to be incorporated into niche applications for transparent electrodes in photovoltaic cells or flexible displays and eventually be used with silicon in computer chips as interconnect wiring or heat spreaders.
“The important finding is the possibility of a strong enhancement of thermal conduction properties of isotopically pure graphene without substantial alteration of electrical, optical and other physical properties,” Balandin said. “Isotopically pure graphene can become an excellent choice for many practical applications provided that the cost of the material is kept under control.”