Synergistic effect of In doping on electrical and thermal properties of Cu2SnSe3 thermoelectric system

• Published in: Journal of materials science. Materials in electronics Vol. 32; no. 6; pp. 6955 - 6964
• Main Authors: Thomas, Riya, Rao, Ashok, Jiang, Zhao-Ze, Kuo, Yung-Kang
• Format: Journal Article
• Language: English
• Published: New York Springer US 01.03.2021; Springer Nature B.V
• Subjects: Characterization and Evaluation of Materials; Chemistry and Materials Science; Doping; Electrical resistivity; Electromagnetism; Figure of merit; Hall effect; Heat conductivity; Investigations; Materials Science; Optical and Electronic Materials; Phonons; Point defects; Power factor; Room temperature; Seebeck effect; Synergistic effect; Temperature; Thermal conductivity; Thermodynamic properties; Thermoelectric materials; Thermoelectricity; Transport properties
• ISSN: 0957-4522; 1573-482X
• DOI: 10.1007/s10854-021-05402-x

Cu 2 SnSe 3 has been considered as a potential thermoelectric material owing to its tunable transport properties and its phonon-glass-electron-crystal (PGEC) characteristics. Here, p -type pure and In-doped Cu 2 SnSe 3 samples are synthesized by the solid-state sintering technique. Cubic structure with F 4 ¯ 3 m space group is maintained for all the samples, and a linear increase in lattice parameter with increasing In concentration has been observed. The nature of electrical resistivity changes from semiconducting to metallic behavior for samples with x  > 0.10. The decrease in both electrical resistivity and Seebeck coefficient with an increase in x is attributed to the increased hole concentration. Such a scenario is confirmed from the room-temperature Hall effect measurements. Indium doping also reduces the thermal conductivity of the Cu 2 SnSe 3 system as a result of increased phonon scattering due to the mass fluctuation. Concurrently, enhancement of thermoelectric power factor ( PF ) and figure of merit ( ZT ) is achieved with In doping at Sn site of Cu 2 SnSe 3 . The maximum ZT of 0.04 has been exhibited by the sample with x  = 0.25 at 400 K, which is six times higher than that of the undoped Cu 2 SnSe 3 .