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

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