High-temperature thermoelectric properties of Ca0.92La0.04RE0.04MnO3 (RE = Sm, Dy and Yb) prepared by coprecipitation
Year: 2018
Type: article
Abstract: A series of Ca 0.92 La 0.04 RE 0.04 MnO 3 (RE = Sm, Dy and Yb) compounds are synthesized via a coprecipitation technique. The influence of La/RE dual doping on the phase structure, microstructure and thermoelectric properties of the CaMnO 3 system is investigated. Increased material density with grain sizes of 1–2 μ m and a homogeneous microstructure is realized. Dual doping decreases the electrical resistivity due to an increase in the carrier concentration and also decreases the thermal conductivity due to increased grain scattering, damping of local vibrations by heavier La/RE ions compared to Ca and lattice distortion. The Ca 0.92 La 0.04 Yb 0.04 MnO 3 shows the highest power factor of 3.49 × 10 −4 W m −1 K −2 and the highest dimensionless figure of merit ZT of 0.25 at 770 K, which is approximately 3 times larger than that obtained for the undoped CaMnO 3 and significantly larger than that of single-doped CaMnO 3 prepared by solid-state reaction. This work provides a basic foundation for the industrial application of this thermoelectric material.
Source: Materials Research Express
Authors: Cuiqin Li, Qianlin Chen, Yunan Yan, Yanan Li, Ying Zhao
Institutions: Guizhou University, Guizhou Education University
Language: English
Subfield: Materials Chemistry
Field: Materials Science
Domain: Physical Sciences
Open Access status: bronze
OpenAlex ID: W2783966907