Abo Bibliothek: Guest

ISSN Online: 2377-424X

ISBN CD: 1-56700-226-9

ISBN Online: 1-56700-225-0

International Heat Transfer Conference 13
August, 13-18, 2006, Sydney, Australia

STUDIES ON THERMOPHYSICAL PROPERTIES OF NANOSTRUCTURED MATERIALS

Get access (open in a dialog) DOI: 10.1615/IHTC13.p30.310
20 pages

Abstrakt

The thermophysical properties of nanostructured materials are of importance for basic science as well as for technological applications. In this paper, we, at first, summarize the progress in the studies on the thermophysical properties of nanostructured materials, especially on the thermal conductivity of nanofilms and nanotubes, and then report our experimental studies on the thermal conductivity of suspended metallic nanofilms and individual nanotubes. The in-plane thermal conductivity of suspended metallic nanofilms has been measured with the direct current heating method. The measured results show that there exists a strong size effect on the thermal conductivity and the relation between the thermal conductivity and electrical conductivity of these metallic nanofilms is different from that of the bulk materials and does not follow the Wiedemann-Franz law. This result shows that the effect of the grain boundaries on the ability of electrons to transport heat is different from that to transport charge. The thermal conductivity of individual multiwalled carbon nanotubes has been measured by a novel method using a suspended sample-attached T-type nanosensor. The size effect of the different diameters on the thermal conductivity has been observed experimentally, which indicates that the interactions of phonons and electrons between walls affect the thermal conductivity. Our study has provided two simple and reliable methods to measure the thermal conductivity for any kind of individual nanofilms, nanofibers and nanotubes.