In:
Angewandte Chemie International Edition, Wiley, Vol. 59, No. 12 ( 2020-03-16), p. 4822-4829
Abstract:
A challenge in thermoelectrics is to achieve intrinsically low thermal conductivity in crystalline solids while maintaining a high carrier mobility ( μ ). Topological quantum materials, such as the topological insulator (TI) or topological crystalline insulator (TCI) can exhibit high μ . Weak topological insulators (WTI) are of interest because of their layered hetero‐structural nature which has a low lattice thermal conductivity ( κ lat ). BiTe, a unique member of the (Bi 2 ) m (Bi 2 Te 3 ) n homologous series ( m : n =1:2), has both the quantum states, TCI and WTI, which is distinct from the conventional strong TI, Bi 2 Te 3 (where m : n =0:1). Herein, we report intrinsically low κ lat of 0.47–0.8 W m −1 K −1 in the 300–650 K range in BiTe resulting from low energy optical phonon branches which originate primarily from the localized vibrations of Bi bilayer. It has high μ ≈516 cm 2 V −1 s −1 and 707 cm 2 V −1 s −1 along parallel and perpendicular to the spark plasma sintering (SPS) directions, respectively, at room temperature.
Type of Medium:
Online Resource
ISSN:
1433-7851
,
1521-3773
DOI:
10.1002/anie.202000343
Language:
English
Publisher:
Wiley
Publication Date:
2020
detail.hit.zdb_id:
2011836-3
detail.hit.zdb_id:
123227-7
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