Ab initio study of multifunctional novel CsErZnM₃(M = Se, Te) chalcogenides: potential materials for UV protection and energy harvesting

Abstract Novel quaternary chalcogenides show extraordinary thermal performance and adjustable optoelectronic properties. We employed the density functional theory to study the structural, spin-polarized electronic, optical, and thermoelectric nature of novel CsErZnM 3 (M = Se, Te) quaternary chalcogenides. The calculated phonon dispersion curves, cohesive and formation energies provide indications supporting the stability of these materials. Additionally, the investigation of their band profiles reveals that these materials exhibit a band gap with a semiconductor nature. The high occurrence of Zn-s states indicates that Zn was involved in major bonding interactions. The substantial role of Se-p and Te-p states also suggests strong covalent interactions with Zn atoms, as well as with Er. The materials demonstrate potential as active UV-reflecting materials, evidenced by the distinctive peaks in their computed reflection spectra and suggesting their possible applications in UV protection technologies. These materials consistently display p-type conductivity as confirmed by their positive Seebeck coefficients. The combination of the presently studied properties including the stability, direct band gap nature, tunable optoelectronic behaviors, and exceptional thermal performance suggests that these quaternary chalcogenides can have substantial potential for numerous applications in materials science and engineering.