Enhanced photoluminescence emission from XSO 4 :Eu 2+ (X = Mg, Sr) microphosphors

Microcrystalline powder of pure and Eu 2+ doped MgSO 4 and SrSO 4 samples were prepared by high temperature re-crystallization method. X-ray diffraction, Scanning electron microscopy, energy dispersive spectroscopy and Fourier transform infrared spectroscopy studies were used to investigate the structural properties of prepared samples. It was observed that, in both cases, undoped and Eu 2+ doped samples had same crystal structure confirming that small amount of rare earth ion doping did not change the basic structure of crystal. For optical characterization, photoluminescence (PL) and diffuse reflectance spectra of these samples were analyzed. The diffuse reflectance analysis was used to study bandgap of XSO 4 :Eu 2+ samples. Many fold enhancement of PL emission peak was observed in doped sample when compared with undoped sample. These high intense spectra may have many uses in optoelectronic display devices. The enhancement mechanism was discussed in this paper.