Multifunctional properties of ZrPdSn half-Heusler alloy: A first-principles study for sustainable technologies

This work presents a comprehensive first-principles study of the half-Heusler compound ZrPdSn, focusing on its structural, electronic, optical, and thermoelectric properties. Formation energy and elastic constants confirm its thermodynamic and mechanical stability, while the negligible magnetic moment establishes a non-magnetic ground state. Electronic structure analysis reveals an indirect bandgap of ∼0.50 eV (mBJ), highlighting its semiconducting nature. Optical spectra show strong ultraviolet absorption originating from Sn-p → Zr/Pd-d transitions and high infrared transparency, making ZrPdSn a promising candidate for solar cells, optical coatings, and IR-based devices. Thermoelectric predictions based on BoltzTraP calculations indicate a favorable Seebeck coefficient and promising ZT values; however, we explicitly acknowledge the limitation that only the electronic contribution to thermal conductivity (κe) is considered, while the lattice contribution (κL) remains to be quantified. Taken together, these results position ZrPdSn as a multifunctional, non-magnetic half-Heusler with potential for sustainable optoelectronic and energy-conversion technologies, pending further finite-temperature validation.