α-(Y,Gd)FS:Ce³⁺: A novel red-emitting fluorosulfide phosphor for solid-state lighting

A novel Ce³⁺-doped fluorosulfide phosphor, α-(Y,Gd)FS: Ce³⁺, was first investigated as a new candidate for application in phosphor-converted light emitting diodes (LEDs) and thin-film electroluminescence (TFEL) devices. The detailed crystal structure was investigated based on X-ray diffraction profiles using Rietveld refinement methods. This phosphor shows good absorption ranging from ultraviolet to visible region and broad saturated red emission, which can be tuned from 660 to 672 nm, and the photoluminescence (PL) intensity was demonstrated to be effectively enhanced by Gd³⁺ substitution.