Electronic, elastic, optic, thermal dynamic, and thermoelectric properties of the half-Heusler compounds ZrCoBi and TiCoBi

In this study, the electronic energy band, elastic, optic, thermal dynamic, and thermoelectric properties of two half-Heusler alloys ZrCoBi and TiCoBi were investigated by using density functional theory. The phonon dispersion and elastic constants confirmed that ZrCoBi and TiCoBi were dynamically and mechanically stable. The elastic constants showed that these two half-Heuslers had better plasticity and that the mechanical properties were strongly direction dependent. In addition, the optics were thoroughly discussed, and ZrCoBi and TiCoBi were found to be promising optical materials. Finally, the thermal characteristics and thermoelectric properties of the materials were investigated and fully analysed. Our investigation demonstrated that both ZrCoBi and TiCoBi were p-type thermoelectric materials.