A Solution Processable High-Performance Thermoelectric Copper Selenide Thin Film

Zhaoyang Lin; Courtney Hollar; Joon Sang Kang; Anxiang Yin; Yiliu Wang; Hui-Ying Shiu; Yu Huang; Yongjie Hu; Yanliang Zhang; Xiangfeng Duan

doi:10.1002/adma.201606662

A Solution Processable High-Performance Thermoelectric Copper Selenide Thin Film

Adv Mater. 2017 Jun;29(21). doi: 10.1002/adma.201606662. Epub 2017 Mar 29.

Authors

Affiliations

¹ Department of Chemistry and Biochemistry, California NanoSystems Institute, University of California, Los Angeles, CA, 90095, USA.
² Department of Mechanical and Biomedical Engineering, Boise State University, ID, 83725, USA.
³ Department of Mechanical and Aerospace Engineering, University of California, Los Angeles, CA, 90095, USA.
⁴ Department of Materials Science and Engineering, California NanoSystems Institute, University of California, Los Angeles, CA, 90095, USA.

PMID: 28370460
DOI: 10.1002/adma.201606662

Abstract

A solid-state thermoelectric device is attractive for diverse technological areas such as cooling, power generation and waste heat recovery with unique advantages of quiet operation, zero hazardous emissions, and long lifetime. With the rapid growth of flexible electronics and miniature sensors, the low-cost flexible thermoelectric energy harvester is highly desired as a potential power supply. Herein, a flexible thermoelectric copper selenide (Cu₂ Se) thin film, consisting of earth-abundant elements, is reported. The thin film is fabricated by a low-cost and scalable spin coating process using ink solution with a truly soluble precursor. The Cu₂ Se thin film exhibits a power factor of 0.62 mW/(m K² ) at 684 K on rigid Al₂ O₃ substrate and 0.46 mW/(m K² ) at 664 K on flexible polyimide substrate, which is much higher than the values obtained from other solution processed Cu₂ Se thin films (<0.1 mW/(m K² )) and among the highest values reported in all flexible thermoelectric films to date (≈0.5 mW/(m K² )). Additionally, the fabricated thin film shows great promise to be integrated with the flexible electronic devices, with negligible performance change after 1000 bending cycles. Together, the study demonstrates a low-cost and scalable pathway to high-performance flexible thin film thermoelectric devices from relatively earth-abundant elements.

Keywords: copper selenide; flexible; solution process; thermoelectric; thin film.