Comprehensive calculations and prominent thermoelectric properties of Li3P and Li3As

Abstract

Based on first-principles calculations, together with the Boltzmann transport equation and semiclassical analysis, we carried out a series of studies on the thermoelectric properties of Li3P and Li3As, such as the thermal conductivity κ which contains lattice thermal conductivity κL and electronic thermal conductivity κe, electron structure, Seebeck coefficient S and electrical conductivity σ, and obtained extremely large Seebeck coefficient S and extraordinary low lattice conductivity κL which are 2.832 Wm−1K−1 and 2.795 Wm−1K−1 at a temperature of 300 K for Li3P and Li3As, respectively. Benefited from the intrinsic flat band structure near the Fermi level and the drastic anharmonic phonon scattering, we finally acquired ideal figure of merit ZT values, which are 1.17 and 1.13 for p-type doped Li3P and Li3As, respectively, the above results indicate that Li3P and Li3As are promising thermoelectric materials if properly used in the future.