Phosphors fabricated from one or more layers of a naturally lamellar or fabricated lamellar semiconductor that is combined with a substrate. One or more of the layers of the lamellar semiconductor are separated from bulk material. The one or more layers are transformed into a phosphor for use with one or more light-emitting devices for the purpose of modifying the light emitted by the light-emitting device(s). Such transformation can be effected in a variety of ways, such as precise thinning or thickening of the removed layer(s) and/or intercalating one or more species of ions into the layer(s) that function as phosphors.