Thermoelectric performance of binary lithium-based compounds: Li3Sb and Li3Bi

Thermoelectric transport properties of binary lithium-based compounds Li3Sb and Li3Bi are investigated. Although the present results show zTs (0.3 for Li3Sb and 0.06 for Li3Bi) are low for the p-type compounds in this family, the experimental data analysis based on the single parabolic band model assuming the dominance of acoustic phonon scattering for carriers suggests that both Li3Sb and Li3Bi process good electronic quality factor BE over 3, which gives rise to the predicted peak zT values above 0.7 and 1.2 at 800 K for Li3Sb and Li3Bi, respectively. In addition, the electronic band structure and phonon dispersion of Li3Sb are given by first principles calculation. This work offers insight into the crystal structure and transport properties of Li3Sb and Li3Bi, indicating the potential of binary lithium-based compounds as promising thermoelectrics.