An Ab-Initio Study of LiTaRhX (X=Al,Ga) for high-temperature thermoelectric applications with enriched material properties

The presenting research outlet is being focused on the detailed research prospectus of the recently discovered Li based (18 Valence Electron Count rule follower) quaternary Heusler compounds, i.e. LiTaRhAl and LiTaRhGa, within the Boltzmann transport equations and the theoretical research reach of Density Functional Theory. Both the materials get stabilized with the FCC structure of F-43 group with the energy band gaps of 0.31 (LiTaRhAl) and 0.88 (LiTaRhGa) and were found in p-type semiconducting features. The favorable material properties like phonon dispersion curves, thermodynamic responses, elastic and mechanical features, evaluation of the isotropic behavior, and the high melting points 1902 ± 300K (LiTaRhAl) and 1934 ± 300K (LiTaRhGa) are awaking interest for the high-temperature applications. Finally, this idea results the surprising Seebeck coefficient values (1349.2 µV/K for LiTaRhAl and 1890 µV/K for LiTaRhGa) at 300K and then the figure of merit (0.55 for LiTaRhAl, 0.66 for LiTaRhGa) at 1700K with the Cauchy’s pressure values (0.3 for LiTaRhAl and 23.1 for LiTaRhGa) along with the Pugh’s ratio values which declared the suitability of the materials for the fabrication of high temperature ductile natured thermoelectric modules (TEMs). This is the first time research platform where these recently discovered compounds are being evaluated (in-depth leaflet) for high-temperature thermoelectric applications with enriched material properties for practical energy conversion applications.