Work

Influence of contact resistance and heat leakage in the determination of the dimensionless figure of merit via duo-impedance spectroscopy

Year: 2021

Type: article

Abstract: The influence of contact resistance between a polycrystalline bismuth as a basic thermoelectric material and electrodes made of copper using binders of Ag epoxy and conventional solder was investigated to estimate the dimensionless figure of merit ( zT ) via impedance spectroscopy (IS). The frequency dependence of the impedance using both binders was measured at 300 K under an appropriate alternating current because a considerably larger Peltier heat was required, relative to Joule heat, for estimating the zT precisely. Through the duo-IS method, zT at 300 K was estimated to be 0.126 ± 0.004 and 0.130 ± 0.002 using the Ag epoxy and solder, respectively. The temperature dependence of zT from 300 to 30 K was also estimated, and zT > 0.01 was a practical based on this technique, owing to its signal–noise ratio. The duo-IS method is invaluable for estimating zT in the entire temperature region based on an appropriate configuration.

Source: Japanese Journal of Applied Physics

DOI: 10.35848/1347-4065/ac1f48

Authors: Shinya Hirabayashi, Yasuhiro Hasegawa

Institution: Saitama University

Language: English

Topic: Advanced Thermoelectric Materials and Devices

Subfield: Materials Chemistry

Field: Materials Science

Domain: Physical Sciences

Open Access status: bronze

Funders: Iketani Science and Technology Foundation, Japan Society for the Promotion of Science

Awards: Study for giant Seebeck coefficient using one-dimensional single crystam bismuth quantum nanoiwire by nano-fabrication, Transport phenomena in bismuth nanowires