Improvement of Thermoelectric properties of Lanthanum cobaltate by Sr and Mn co-substitution

TL;DR

This study investigates how co-substituting Sr and Mn into LaCoO3 enhances its thermoelectric properties, achieving a maximum figure of merit of 0.14 at 480 K, with implications for thermoelectric material development.

Contribution

It introduces a co-substitution strategy in LaCoO3 to improve thermoelectric performance, demonstrating the effects on electrical and thermal conductivities.

Findings

Electrical conductivity increased with co-substitution.

Thermal conductivity decreased due to phonon scattering.

Maximum figure of merit of 0.14 at 480 K achieved.

Abstract

We report thermoelectric (TE) properties of Sr and Mn co-substituted LaCoO3 system from room temperature to 700 K. Sr-substitutions at La and Mn at Co site in LaCoO3 improves the electrical conductivity ({\sigma}). Thermal conductivity (\k{appa}) of all the samples increases with the increase in temperature but decreases with the substitution in LaCoO3. An estimation of the electronic thermal conductivity (\k{appa}e) suggests a dominant phonon contribution to thermal conductivity in this system. A maximum value of the figure of merit is 0.14 at 480 K for La0.95Sr0.05Co0.95Mn0.05O3