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Thermoelectric Properties of n-Type Bi₄O₄SeX₂ (X = Cl, Br).

ABSTRACT: The multiple anion superlattice Bi₄O₄SeCl₂ has been reported to exhibit extremely low thermal conductivity along the stacking c-axis, making it a promising material for thermoelectric applications. In this study, we investigate the thermoelectric properties of Bi₄O₄SeX₂ (X = Cl, Br) polycrystalline ceramics with different electron concentrations by adjusting the stoichiometry. Despite optimizing the electric transport, the thermal conductivity remained ultra-low and approached the Ioffe-Regel limit at high temperatures. Notably, our findings demonstrate that non-stoichiometric tuning is a promising approach for enhancing the thermoelectric performance of Bi₄O₄SeX₂ by refining its electric transport, resulting in a figure of merit of up to 0.16 at 770 K.

SUBMITTER: Wang T

PROVIDER: S-EPMC10303193 | biostudies-literature | 2023 Jun

REPOSITORIES: biostudies-literature

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Thermoelectric Properties of n-Type Bi4O4SeX2 (X = Cl, Br).

Wang Tao T Hu Wanghua W Lou Zhefeng Z Xu Zhuokai Z Yang Xiaohui X Le Tian T Wang Jialu J Lin Xiao X

Materials (Basel, Switzerland) 20230612 12

The multiple anion superlattice Bi4O4SeCl2 has been reported to exhibit extremely low thermal conductivity along the stacking c-axis, making it a promising material for thermoelectric applications. In this study, we investigate the thermoelectric properties of Bi4O4SeX2 (X = Cl, Br) polycrystalline ceramics with different electron concentrations by adjusting the stoichiometry. Despite optimizing the electric transport, the ...[more]

PMID: 37374512

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