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Heavy Doping by Bromine to Improve the Thermoelectric Properties of n-type Polycrystalline SnSe.

ABSTRACT: Single crystal tin selenide (SnSe) has attracted much attention for its excellent thermoelectric performance. However, polycrystalline SnSe exhibits unsatisfactory figure-of-merit due to the inferior electrical properties, especially for n-type SnSe. In this work, a high concentration of Br doping (6-12 atm%) on the Se site effectively increases the Hall carrier concentration from 1.6 × 10¹⁷ cm^-3 (p-type) in undoped SnSe to 1.3 × 10¹⁹ cm^-3 (n-type) in Br-doped SnSe_0.88Br_0.12, leading to an increased electrical conductivity close to that of a single crystal. Combined with the decreased lattice thermal conductivity due to the enhanced phonon scattering by composition fluctuation and dislocations, a peak ZT of ?1.3 at 773 K, together with the enhanced average ZT is obtained in SnSe_0.9Br_0.1 along the hot pressing direction.

SUBMITTER: Li S

PROVIDER: S-EPMC6145293 | biostudies-literature | 2018 Sep

REPOSITORIES: biostudies-literature

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Heavy Doping by Bromine to Improve the Thermoelectric Properties of n-type Polycrystalline SnSe.

Li Shan S Wang Yumei Y Chen Chen C Li Xiaofang X Xue Wenhua W Wang Xinyu X Zhang Zongwei Z Cao Feng F Sui Jiehe J Liu Xingjun X Zhang Qian Q

Advanced science (Weinheim, Baden-Wurttemberg, Germany) 20180731 9

Single crystal tin selenide (SnSe) has attracted much attention for its excellent thermoelectric performance. However, polycrystalline SnSe exhibits unsatisfactory figure-of-merit due to the inferior electrical properties, especially for n-type SnSe. In this work, a high concentration of Br doping (6-12 atm%) on the Se site effectively increases the Hall carrier concentration from 1.6 × 1017 cm-3 (p-type) in undoped SnSe to 1.3 × 1019 cm-3 (n-type) in ...[more]

PMID: 30250800

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