Photoluminescence of Sulfide Phosphors with the MB 2 S 4 Composition

Photoluminescence emission spectra and diffuse reflectance absorption spectra were measured on phosphors composed of ternary sulfide hosts with the Th 3 P 4 , calcium ferrite, spinel, and thiogallate structure types each activated by Eu 2+ , Ce 3+ , Ho 3+ , and Mn 2+ . Fourteen of the sixteen materials gave a luminescence characteristic of the activator ion but only SrY 2 S 4 : Eu 2 + , SrY 2 S 4 : Mn 2 + , and ZnGa 2 S 4 : Mn 2 + were intense emitters. The emission spectra can be accounted for by localized states of the activator ions in the sulfide hosts.