Tuning of emission colours in strontium aluminate long persisting phosphor

Solid-state preparation, structure, and multi-colour luminescence of Eu2+ doped strontium aluminate (SRA) phosphors have been reported in this paper. It has been observed that a slight modification in the processing parameters such as type of reducing atmosphere, stoichiometric excess of one or more constituents, nature of fluxes, and intentional addition of carbon or rare-earth halides can drastically shift the emission colours of the SRA phosphor in the visible spectrum. X-ray diffraction analysis and scanning electron microscopy observations of the samples revealed the formation of different crystalline phases related to the SRA system. The luminescence measurements showed that the decay times varied with the emission colours of the samples.