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The work presents down conversion (DC) luminescent properties of pure SrTiO3 (STO) and Eu3+ doped STO prepared by wet chemical reaction sintered at 1100°C. Prepared samples were characterized by FT-IR, UV absorption, XRD, EDX and fluorescent spectroscopy. The FT-IR spectrum of Eu3+ doped STO had absorption bands at 922, 972 and 538 cm-1 indicating the stretching vibration of Sr-O, Eu-O and Ti-O bond, respectively. XRD pattern of SrTiO3 sintered at 1100°C depicted a typical perovskite of cubic symmetry. The EDX spectra confirmed the uniform substitution of Eu3+ in STO. The optical absorption edge of pure SrTiO3 was in UV region. Emission properties were studied by exciting the pure STO and Eu doped STO by 280,325 and 396 nm wavelengths. Eu3+ doping enhanced the emission intensity if STO. Multiple peaks were observed in visible region ranging from 400 to 700m which might be due to defect states present in energy band gap. Therefore visible emissions were obtained from STO and Eu3+ doped STO by exciting with UV light. Visible emission from prepared STO and Eu3+ doped STO powder could be useful in solid state lighting and for display devices.

MgAl2O4 (MAO) spinel has been considered as one of the excellent optoelectronic material due to its excellent mechanical strength and transparency in visible region to IR region. Many studies reported that MAO has F centers generated due to high temperature sintering which resulted in visible emission. The aim of present study is to explore MAO sintered at high temperature for white light emission. MAO was synthesized by sol-gel method sintered at 1400°C high temperature for 4hrs. Prepared MAO was characterized by various characterization techniques; Fourier transfer infrared spectroscopy (FTIR), X-ray diffraction (XRD), Field emission scanning electron microscopy (FESEM) with the energy dispersive X-ray spectroscopy (EDX) and Fluorescence spectroscopy (FS). Peak at 674cm-1 in FTIR confirmed the formation of MAO. SEM Images showed the agglomeration of particles due to high temperature sintering Emission properties of MAO was studied by Florescence spectroscopy. MAO was excited by UV light. The emission spectra showed multicolor emission in visible region due to generation of F centers in the bandgap proving MAO as excellent material for white light emission.