Ultralow thermal conductivity of β-Cu2Se by atomic fluidity and structure distortion

Autor:	Jae Pyung Ahn, Massoud Kaviany, Hyoungchul Kim, Sedat Ballikaya, Ctirad Uher, Hang Chi, Kiyong Ahn
Rok vydání:	2015
Předmět:	Materials science Polymers and Plastics Phonon Electron energy loss spectroscopy Metals and Alloys Thermal conduction Thermoelectric materials Electronic Optical and Magnetic Materials Ion Thermal conductivity Chemical physics Distortion Thermal Ceramics and Composites
Zdroj:	Acta Materialia. 86:247-253
ISSN:	1359-6454
DOI:	10.1016/j.actamat.2014.12.008
Popis:	We demonstrate a prototype thermal evolution path for liquid thermal conductivity in solids. Thermal evolution of β -Cu2Se shows large interstitial displacement of constituent atoms marked by glass-like transitions and an asymptotic liquid thermal transport. Using ab initio molecular dynamics (AIMD), we identify these transitions, and confirm them with in situ transmission electron microscopy and electron energy loss spectroscopy. The thermal disorder of the Cu+ ions forms homopolar Cu–Cu bonds under a rigid Se framework, and at yet higher temperatures the Se framework undergoes thermal distortion. The non-equilibrium AIMD prediction of lattice thermal conductivity shows significant suppression of the phonon transport, in agreement with experiments and molecular behavior.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::8d14fe8c722d6bdbbfa486386bb59361 https://doi.org/10.1016/j.actamat.2014.12.008 Zobrazit plný text záznamu Full Text from ScienceDirect