Influence of Pd Doping on Electrical and Thermal Properties of n-Type Cu0.008Bi2Te2.7Se0.3 Alloys

Se Yun Kim; Hyun-Sik Kim; Kyu Hyoung Lee; Hyun-Jun Cho; Sung-Sil Choo; Seok-Won Hong; Yeseong Oh; Yerim Yang; Kimoon Lee; Jae-Hong Lim; Soon-Mok Choi; Hee Jung Park; Weon Ho Shin; Sang-Il Kim

doi:10.3390/ma12244080

Influence of Pd Doping on Electrical and Thermal Properties of n-Type Cu_0.008Bi₂Te_2.7Se_0.3 Alloys

Materials (Basel). 2019 Dec 6;12(24):4080. doi: 10.3390/ma12244080.

Authors

Se Yun Kim¹, Hyun-Sik Kim², Kyu Hyoung Lee³, Hyun-Jun Cho⁴, Sung-Sil Choo⁴, Seok-Won Hong⁴, Yeseong Oh⁴, Yerim Yang⁴, Kimoon Lee⁵, Jae-Hong Lim⁶, Soon-Mok Choi⁷, Hee Jung Park⁸, Weon Ho Shin⁹, Sang-Il Kim⁴

Affiliations

¹ Samsung Electronics, Suwon 16678, Korea.
² Department of Materials Science and Engineering, Hongik University, Seoul 04066, Korea.
³ Department of Materials Science and Engineering, Yonsei University, Seoul 03722, Korea.
⁴ Department of Materials Science and Engineering, University of Seoul, Seoul 02504, Korea.
⁵ Department of Physics, Kunsan National University, Gunsan 54150, Korea.
⁶ Department of Materials Science and Engineering, Gachon University, Seongnam 13120, Korea.
⁷ School of Energy, Materials and Chemical Engineering, Korea University of Technology and Education, Cheonan 31253, Korea.
⁸ Department of Materials Science and Engineering, Dankook University, Cheonan 31116, Korea.
⁹ Department of Electronic Materials Engineering, Kwangwoon University, Seoul 01897, Korea.

Abstract

Doping is known as an effective way to modify both electrical and thermal transport properties of thermoelectric alloys to enhance their energy conversion efficiency. In this project, we report the effect of Pd doping on the electrical and thermal properties of n-type Cu_0.008Bi₂Te_2.7Se_0.3 alloys. Pd doping was found to increase the electrical conductivity along with the electron carrier concentration. As a result, the effective mass and power factors also increased upon the Pd doping. While the bipolar thermal conductivity was reduced with the Pd doping due to the increased carrier concentration, the contribution of Pd to point defect phonon scattering on the lattice thermal conductivity was found to be very small. Consequently, Pd doping resulted in an enhanced thermoelectric figure of merit, zT, at a high temperature, due to the enhanced power factor and the reduced bipolar thermal conductivity.

Keywords: Pd doping; bipolar thermal conductivity; effective mass; phonon scattering; thermoelectric.

Grants and funding

20180511069/2018 Research Fund of the University of Seoul