A comprehensive comparison study on the vibrational and optical properties of CVD-grown and mechanically exfoliated few-layered WS2

Tungsten disulfide (WS₂), a typical transition metal dichalcogenide (TMDC) material, transits from an indirect to direct bandgap when the thickness is thinned to a monolayer, thereby allowing for applications in transistors, photodetectors, and electroluminescent devices.