Note to users. If you're seeing this message, it means that your browser cannot find this page's style/presentation instructions -- or possibly that you are using a browser that does not support current Web standards. Find out more about why this message is appearing, and what you can do to make your experience of our site the best it can be.

Published Online December 14, 2006
Science DOI: 10.1126/science.1136494

Reports

Submitted on October 19, 2006
Accepted on December 4, 2006

Ultralow Thermal Conductivity in Disordered, Layered WSe2 Crystals

Catalin Chiritescu 1, David G. Cahill 1*, Ngoc Nguyen 2, David Johnson 2, Arun Bodapati 3, Pawel Keblinski 3, Paul Zschack 4

1 Department of Materials Science and Engineering, Frederick Seitz Materials Research Laboratory, University of Illinois, Urbana, IL 61801, USA.
2 Department of Chemistry, University of Oregon, Eugene, OR 97403, USA.
3 Department of Materials Science and Engineering, Rensselaer Polytechnic Institute, Troy, NY 12180, USA.
4 Advanced Photon Source, Argonne National Laboratory, Argonne, IL 60439, USA.

* To whom correspondence should be addressed.
David G. Cahill , E-mail: d-cahill{at}uiuc.edu

The cross-plane thermal conductivity of thin films of WSe2, grown from alternating W and Se layers, is as small as 0.05 watts per meter per Kelvin at room temperature, 30 times smaller than the c-axis thermal conductivity of single-crystal WSe2 and a factor of 6 smaller than the predicted minimum thermal conductivity for this material. We attribute the ultralow thermal conductivity of these disordered, layered crystals to the localization of lattice vibrations induced by the random stacking of two-dimensional crystalline WSe2 sheets. Disordering of the layered structure by ion bombardment increases the thermal conductivity.




To Advertise     Find Products

Science. ISSN 0036-8075 (print), 1095-9203 (online)