Strain-modulated mechanical, electronic, and thermal transport properties of two-dimensional PdS2 from first-principles investigations

Strains can effectively modulate the electronic structure and thermal conductivity of materials. In this work, the electronic structure and thermal conductivity properties of PdS 2 under different strains were investigated using first-principles calculation combined with iterative method for solving Boltzmann transport equation theory. Through phonon spectrum calculations, it is found that PdS 2 is thermodynamically stable in the strain range from 0 to 10%. Interestingly, the strained single-layer PdS 2 transforms from an indirect bandgap semiconductor to a quasi-direct bandgap semiconductor, and the bandgap of PdS 2 decreases to 1.41 eV (decreased by 20.8%). Due to the softening of the phonons and the decreasing of phonons group velocity, the thermal conductivity is reduced with the applied biaxial area strains. Thermal transport investigations reveal that the in-plane thermal conductivity of unstrained PdS 2 is 32.32 Wm − 1 K − 1 . When the area strain reaches 10%, the thermal conductivity of PdS 2 is reduced by nearly twice the ratio of strain. The sensitive strain dependence of bandgap and thermal conductivity indicates that PdS 2 can flexibly select the substrate and match the substrate, and the thermoelectric coefficient can be effectively adjusted, indicating that PdS 2 has good application prospects in thermoelectric, photoelectric, and catalytic materials.