Strained noble metal di chalcogenides PtX2 (X = S, Se) mono-layer: Ab initio study of electronic and lattice dynamic properties

Highlights: • Mono-layers of noble metal di chalcogenides PtX₂ (X = S, Se) were synthesized theoretically. • A linear variation in band gap is observed on applying biaxial strain on it. • A significant modification in the phonon spectrum for biaxial strain of 4% has been observed. Electronic properties of noble metal dichalcogenides PtX₂ (X = S, Se) mono-layers have been studied using plane wave pseudopotential method based on density functional theory. The band gap is observed to be as 1.94 eV (1.37 eV) in case of PtS₂ (PtSe₂) mono-layer which is found to be in close agreement with previous known results. A further variation in band gap is observed in both the two mono-layers on applying biaxial tensile as well as compressional strain. Phonon spectrum of these mono-layers and its strained structure reflects its dynamical stability.