NDL team has discovered that graphene, a single plane layer of carbon atoms arranged in honey-comb lattice, manifests extremely high thermal conductivity exceeding that of diamond and carbon nanotubes. Carbon nanotubes were previously believed to be the best heat conductors among solids.
The measurement of graphene, an object just one atom thick, required the development of a completely new experimental technique and data extraction methodology.
These measurements were performed using a non-contact optical method based on the micro-Raman spectroscopy. A single atomic-layer graphene flake was suspended across a trench in a silicon wafer and heated with laser light in the middle. The temperature of the sample was determined from the change in the spectral features of the light scattered by graphene. The unique experiment conducted in Balandin's Nano-Device Laboratory was featured by news organizations world-wide.
The superb heat conducting property of graphene may have major practical implications. The high thermal conductivity, coupled with graphene's flat geometry and demonstrated integration with silicon, suggest that graphene can be used for hot-spot cooling and thermal management of nanometer scale electronic devices and circuits.
Link to Nano Letters