Seminars

2013-02-26

Thermal Transport in Graphene and Other Two-Dimensional Layered Materials

Prof. Li Shi, University of Texas at Austin - Dept. of Mechanical Engineering
Speaker's Website
Assoc. Prof Jihui Yang, Dept. of Materials Science and Engineering

Graphene and other two-dimensional (2D) layered materials are being employed for fabricating electronic, energy, and other functional devices. The performance of many of these devices is dictated by thermal transport properties of the 2D building blocks. It has been suggested that the basal-plane thermal conductivity of suspended few-layer graphene and hexagonal boron nitride (h-BN) increases with decreasing thickness, and can exceed the already record-high values of graphite and bulk h-BN. However, these 2D materials are usually supported on a substrate or embedded in a medium for device applications. Hence, the effects of interface interaction on thermal transport in and across 2D building blocks must be understood. Here, we show that the basal-plane thermal conductivity decreases with decreasing thickness of few-layer graphene and h-BN in contact with an amorphous material, as well as bismuth telluride nanoplates with surface oxide. In addition, because internal interface thermal resistance is minimized in ultrathin-graphite foams, the thermal conductivity of the covalently bonded three-dimensional architecture greatly exceeds those of van der Waals-bonded carbon nanostructure networks that have been developed for thermal management.