Raman-Based Steady-State Thermal Characterization of Multiwall Carbon Nanotube Bundle and Buckypaper.

Electrical methods for thermal characterization, like 3ω method, micro-bridge method and TET method have been widely used in the thermal property measurement, while always been limited by the electrical conductance of samples or other temperature dependent thermal resistors. As an optical method, Raman thermometry has been developed and broadly applied in thermal characterization in recent years. In this work, we present a steady-state method based on Raman spectroscopy for the localized thermal characterization of micro/nanowires and thin film materials, respectively. The physical models are developed and two kinds of materials: a MWCNT bundle and a piece of buckypaper are measured to validate this method. The thermal conductivities are measured as 4.92 W/m K and 0.83 W/m K for CNT bundle and buckypaper respectively. Compared with other optical methods, this steady-state Raman method features easy and fast way for thermal characterization, being capable of measuring samples from millimeters down to nanometers.