Record low thermal conductivity of polycrystalline MoS2 films : tuning the thermal conductivity by grain orientation
Sledzinska, Marianna (Institut Català de Nanociència i Nanotecnologia)
Quey, Romain (Centre national de la recherche scientifique. École nationale supérieure des mines de Saint-Étienne)
Mortazavi, Bohayra (Bauhaus-Universität Weimar. Institute of Structural Mechanics)
Graczykowski, Bartlomiej (Adam Mickiewicz University. NanoBioMedical Centre (Poland))
Placidi, M. (Institut de Recerca en Energia de Catalunya)
Saleta Reig, David (Institut Català de Nanociència i Nanotecnologia)
Navarro Urrios, Daniel (Institut Català de Nanociència i Nanotecnologia)
Alzina, Francesc (Institut Català de Nanociència i Nanotecnologia)
Colombo, Luciano (Università di Cagliari. Dipartimento di Fisica)
Roche, Stephan (Institut Català de Nanociència i Nanotecnologia)
Sotomayor Torres, Clivia M. (Institut Català de Nanociència i Nanotecnologia)

Date:	2017
Abstract:	We report a record low thermal conductivity in polycrystalline MoS obtained for ultrathin films with varying grain sizes and orientations. By optimizing the sulfurization parameters of nanometer-thick Mo layers, five MoS films containing a combination of horizontally and vertically oriented grains, with respect to the bulk (001) monocrystal, were grown. From transmission electron microscopy, the average grain size, typically below 10 nm, and proportion of differently oriented grains were extracted. The thermal conductivity of the suspended samples was extracted from a Raman laser-power-dependent study, and the lowest value of thermal conductivity of 0. 27 W m K, which reaches a similar value as that of Teflon, is obtained in a polycrystalline sample formed by a combination of horizontally and vertically oriented grains in similar proportion. Analysis by means of molecular dynamics and finite element method simulations confirm that such a grain arrangement leads to lower grain boundary conductance. We discuss the possible use of these thermal insulating films in the context of electronics and thermoelectricity.
Grants:	European Commission 604668 European Commission 615132 Ministerio de Ciencia e Innovación FIS2015-70862-P Ministerio de Economía y Competitividad SEV-2013-0295 European Commission 696656 Ministerio de Economía y Competitividad FIS2015-67767-P Ministerio de Economía y Competitividad RYC-2014-15392
Rights:	Tots els drets reservats.
Language:	Anglès
Document:	Article ; recerca ; Versió sotmesa a revisió
Published in:	ACS applied materials & interfaces, Vol. 9, Issue 43 (November 2017) , p. 37905-37911, ISSN 1944-8252

DOI: 10.1021/acsami.7b08811

Preprint 13 p, 1.2 MB

The record appears in these collections:
Research literature > UAB research groups literature > Research Centres and Groups (research output) > Experimental sciences > Catalan Institute of Nanoscience and Nanotechnology (ICN2)
Articles > Research articles
Articles > Published articles