Intrinsically high thermoelectric figure of merit of half-Heusler ZrRuTe

The electronic structure and thermoelectric properties of ZrRuTe-based half-Heusler compounds are studied using density functional theory and Boltzmann transport formalism. Based on rigorous computations of electron relaxation timeτconsidering electron-phonon interactions and lattice thermal conductivityκ_lconsidering phonon-phonon interactions, we find ZrRuTe to be an intrinsically good thermoelectric material. It has a high power factor of ∼2 × 10^-3W m^-1K^-2and lowκ_l∼ 10 W m^-1K^-1at 800 K. The thermoelectric figure of meritZT∼ 0.13 at 800 K is higher than similar other compounds. We have also studied the properties of the material as a function of doping and find the thermoelectric properties to be substantially enhanced for p-doped ZrRuTe with theZTvalue raised to ∼0.2 at this temperature. The electronic, thermodynamic, and transport properties of the material are thoroughly studied and discussed.