Enhancing thermoelectric performance of CaMnO3 through a Y- and La- dual-doping strategy
Parisa Amirkhizi, M. A. Madre, Óscar J. Durá, M.A. Torres, A. Sotelo, Andrei V. Kovalevsky, Sh. Rasekh
Abstract
A classical ceramic route has been used in this work to prepare Y and La co-doped CaMnO 3 thermoelectric compound seeking to improve its thermoelectric properties. The study highlights significant improvements in electrical and thermal transport properties achieved with minimal doping levels and a cost-effective synthesis process. The co-doping strategy effectively reduced electrical resistivity (reaching 10.8 mΩ cm at 800 °C for 0.03 (Y, La)-doped samples) while maintaining a relatively high Seebeck coefficient (300 μV/K at 800 °C for 0.01 (Y, La)-doped samples). Moreover, the thermal conductivity was minimized (1.65 W/(K m) at 800 °C for 0.03 (Y, La)-doped samples), leading to outstanding thermoelectric performance, with 0.47 mW/(K 2 m) power factor, and 0.25 ZT values at 800 °C (for 0.01 (Y, La)-doped samples. These results are among the best values reported so far for this family of compounds, underscoring the potential of this material for high-temperature thermoelectric applications and the efficiency of the classical ceramic approach with reduced dopant usage.