Work

Temperature and isotope effects on the thermoelectric properties in SnTe

Year: 2017

Type: article

Abstract: The temperature and Sn isotope effects on SnTe are investigated using the hybrid scheme that combines ab initio molecular dynamics and lattice dynamics (AIMD + LD). The unstable softening of TA phonon mode at 0 K in cubic phase SnTe disappears and the TO mode is stiffened by considering the temperature effect, in agreement with the inelastic neutron scattering (INS) observations. A linear dependence on isotope mass of phonon frequency, lifetime, and mean free path for isolate phonon mode is observed with the possibility of positive, negative, and nearly zero shifts. The lattice thermal conductivity ( κ l a t ) shows saturation characteristic as Sn isotope mass increases to 120 SnTe, with an increase rate of ∼2.1% from 112 SnTe to 124 SnTe. Considering the effects of partial isotope doping, we obtain a reduced κ l a t with respect to the undoped case. The κ l a t is reduced by ∼14.6% at 600 K when considering the volumetric expansion.

Source: Journal of Physics Condensed Matter

DOI: 10.1088/1361-648x/aa63a9

Authors: Yong Lu, Fawei Zheng, Ping Zhang, Xiaohong Shao, Dong-Bo Zhang

Institutions: Beijing University of Chemical Technology, Institute of Applied Physics and Computational Mathematics, Beijing Computational Science Research Center

Language: English

Topic: Advanced Thermoelectric Materials and Devices

Subfield: Materials Chemistry

Field: Materials Science

Domain: Physical Sciences

Open Access status: bronze

Funder: National Natural Science Foundation of China

Award: G682066871