Effects of Cl-Doping on Thermoelectric Transport Properties of Cu2Se Prepared by Spark Plasma Sintering

• Published in: Journal of electronic materials 2019-04, Vol.48 (4), p.1958-1964
• Main Authors: Kim, Min Ji, Lee, Gil-Geun, Kim, Woochul, Kim, Kyomin, Tak, Jang-Yeul, Shin, Weon Ho, Seo, Won-Seon, Hong, Jisang, Lim, Young Soo
• Format: Article
• Language: English
• Subjects: Characterization and Evaluation of Materials; Chemistry and Materials Science; Copper chloride; Copper selenides; Doping; Electrical resistivity; Electronics and Microelectronics; Instrumentation; International Conference on Thermoelectrics 2018; Materials Science; Operating temperature; Optical and Electronic Materials; Plasma sintering; Seebeck effect; Solid State Physics; Spark plasma sintering; Thermal conductivity; Thermodynamic properties; Thermoelectricity; Topical Collection: International Conference on Thermoelectrics 2018; Transport properties
• ISSN: 0361-5235; 1543-186X
• DOI: 10.1007/s11664-018-6708-5

We present the thermoelectric transport properties of Cl-doped Cu 2 Se 1− x Cl x ( x  = 0–0.08) compounds prepared by spark plasma sintering. Cl-doping resulted in a decrease in the electrical conductivity and an increase in the Seebeck coefficient of the compound due to the donor role of Cl. Furthermore, the incorporation of Cl caused the formation of a secondary CuCl phase, which affected the structural, electrical, and thermal properties of the compounds significantly. Although the melting of CuCl limited the operating temperature to ∼ 620 K, the Cl-doped compounds exhibited significantly reduced lattice thermal conductivity because of the presence of the CuCl secondary phase. The highest ZT of 0.6 at 620 K was achieved in Cu 2 Se 0.92 Cl 0.08 , and the effects of CuCl on the thermoelectric transport properties of Cl-doped Cu 2 Se 1− x Cl x compounds are discussed in detail.