| Title |
Enhancing Thermoelectric Performance in Cu0.9Ag0.1InTe2 via CdTe Alloying: Carrier Activation and Suppressed Lattice Thermal Conductivity |
| Authors |
김윤재(Yunjae Kim) ; (Vasudevan Rathinam) ; 이관형(Gwan Hyeong Lee) ; 박재우(Jaewoo Park) ; 김우재(Woojae Kim) ; 김상일(Sang-il Kim) |
| DOI |
https://doi.org/10.3365/KJMM.2026.64.8.744 |
| ISSN |
1738-8228(ISSN), 2288-8241(eISSN) |
| Keywords |
Alloying; CuInTe2; Thermal conductivity; Thermoelectric |
| Abstract |
Chalcopyrite CuInTe2 has emerged as a promising p-type thermoelectric material due to its intrinsically low thermal conductivity. However, its practical application is fundamentally hindered by an inherently low carrier concentration, leading to a restricted power factor. Herein, we present a synergistic optimization strategy to enhance the low-to-intermediate temperature thermoelectric performance of the Ag pre-doped CuInTe2, Cu0.9Ag0.1InTe2 system by CdTe alloying. A series of (Cu0.9Ag0.1InTe2)1-x(CdTe)2x solid solutions (x = 0.00, 0.05, 0.10, 0.15, and 0.20) were successfully synthesized using a conventional solid-state reaction combined with spark plasma sintering. X-ray diffraction confirms the successful formation of the single-phase (Cu0.9Ag0.1InTe2)1-x(CdTe)2x solid solutions, also reveals the systematic lattice expansion upon alloying. The incorporation of Ag at the Cu sites profoundly optimizes the hole carrier concentration, drastically increasing it to optimal levels (~10^19 cm-3) and thus substantially enhancing the electrical conductivity and power factor within the low-to-intermediate temperature regime (300-500 K). Concurrently, the solid solution alloying introduces severe mass and strain field fluctuations, which dominate point-defect scattering and effectively suppress the lattice thermal conductivity across the entire temperature range. Consequently, the synergistic effect of carrier activation and phonon suppression yields improved thermoelectric figure of merit (zT) at low-to-intermediate temperatures. |