Premium
Interstitial Point Defect Scattering Contributing to High Thermoelectric Performance in SnTe
Author(s) -
Pei Yanzhong,
Zheng Linglang,
Li Wen,
Lin Siqi,
Chen Zhiwei,
Wang Yanying,
Xu Xiangfan,
Yu Hulei,
Chen Yue,
Ge Binghui
Publication year - 2016
Publication title -
advanced electronic materials
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.25
H-Index - 56
ISSN - 2199-160X
DOI - 10.1002/aelm.201600019
Subject(s) - phonon scattering , materials science , thermoelectric effect , condensed matter physics , crystallographic defect , thermoelectric materials , scattering , interstitial defect , phonon , thermal conductivity , amorphous solid , solid solution , optoelectronics , crystallography , thermodynamics , composite material , optics , physics , chemistry , metallurgy , doping
Due to point defect phonon scattering, formation of solid solutions has long been considered as an effective approach for enhancing thermoelectric performance through reducing the lattice thermal conductivity. The scattering of phonons by point defects mainly comes from the mass and strain fluctuations between the guest and the host atoms. Both the fluctuations can be maximized by point defects of interstitial atoms and/or vacancies in a crystal. Here, a demonstration of phonon scattering by interstitial Cu atoms is shown, leading to an extremely low lattice thermal conductivity of 0.5 W m −1 K −1 in SnTe‐Cu 2 Te solid solutions. This is the lowest lattice thermal conductivity reported in SnTe‐based materials so far, which is actually approaching the amorphous limit of SnTe. As a result, a peak thermoelectric figure of merit, zT , higher than 1 is achieved in Sn 0.94 Cu 0.12 Te at 850 K, without relying on other approaches for electrical performance enhancements. The strategy used here is believed to be equally applicable in thermoelectrics with interstitial point defects.