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Anomalous thermoelectricity in strained Bi2Te3 films.

ABSTRACT: Bi2Te3-based alloys have been intensively used for thermoelectric coolers and generators due to their high Seebeck coefficient S. So far, efforts to improve the S have been made mostly on changing the structures and components. Herein, we demonstrate an anomalous thermoelectricity in strained Bi2Te3 films, i.e., the value of S is obviously changed after reversing the direction of temperature gradient. Further theoretical and experimental analysis shows that it originates from the coupling of thermoelectric and flexoelectric effects caused by a stress gradient. Our finding provides a new avenue to adjust the S of Bi2Te3-based thermoelectric materials through flexoelectric polarization.

SUBMITTER: Liu Y

PROVIDER: S-EPMC5013394 | biostudies-other | 2016

REPOSITORIES: biostudies-other

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Anomalous thermoelectricity in strained Bi2Te3 films.

Liu Yucong Y Chen Jiadong J Deng Huiyong H Hu Gujin G Zhu Daming D Dai Ning N

Scientific reports 20160907

Bi2Te3-based alloys have been intensively used for thermoelectric coolers and generators due to their high Seebeck coefficient S. So far, efforts to improve the S have been made mostly on changing the structures and components. Herein, we demonstrate an anomalous thermoelectricity in strained Bi2Te3 films, i.e., the value of S is obviously changed after reversing the direction of temperature gradient. Further theoretical and experimental analysis shows that it originates from the coupling of the ...[more]

PMID: 27600406

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