Looking for new semiconductors among the TMX intermetallic using high-throughput calculations

International audience; Novel high-performance materials are needed for developing thermoelectric devices. Oneway to answer this need is to screen a large number of compounds by first-principlescalculations and to synthesize the most promising compounds.We focus our investigation on the ternary intermetallic compounds T-M-X, with T a transitionmetal, a rare earth or an alkaline earth metal, M an element from the first line of thetransition metal and X, a metalloid. For each prototype, all the possible T-M-X combinationsare investigated by DFT calculations. Among all these candidates, those which arepredicted as thermodynamically unstable and metallic are dismissed. For the mostpromising compounds, predicted as stable and semiconductor, complementary calculationsas the phonon band structure and additional BoltzTrap electronic transport calculations arecarried out to better assess their thermoelectric properties. After those theoretical steps,experimental investigations are performed to confirm calculations.The study of the equimolar TMX in four different prototypes lead to the investigation of 2280possible configurations. Then our screening process allowed us to highlight more than 45possible new semiconductors. Among these, new compositions such as HfCoP, SrCuSb orTaFeSb were predicted to be stable and non-metallic. Complementary calculations allowedto estimate their lattice thermal conductivity and Seebeck coefficient.