SYNTHESIS AND CHARACTERIZATION OF SR(1-X) TEO3: XEU3+ PHOSPHORS FOR POTENTIAL SOLID-STATE LIGHTING APPLICATIONS

The Sr(1-x)TeO3:xEu2O3 phosphors were synthesized using the conventional high-temperature solid-state reaction method at 800°C for 3 h in air atomosphere. The assynthesized phosphors were characterizated using XRD, FTIR, absorption spectra, photoluminescence, and X-ray-induced luminescence. Rigaku SmartLab-SE XRD diffractometers confirmed the crystalline nature of the phosphors. From the study, it was found that the structure of the sample was a mixture of SrTeO3 and TeO2. The increased concentration of Eu2O3 seems to contribute to the enhancement or stabilization of SrTeO3 phase. The UV-VIS-NIR spectrophotometer in reflection mode measured the absorption spectrum, revealing six peaks corresponding to energy transitions of Eu3+ ions at 394, 465, 536, 592, 2,207, and 2,070 nm. Photoluminescence analysis demonstrated the strongest luminescence intensity of Eu3+ ions at 614 nm (7F2) under 465 nm excitation, resulting in an overall red emission in the CIE 1931 chromaticity. Combining these findings, Sr(1-x)TeO3: xEu phosphors exhibit promising characteristics for solid-state lighting applications (SSL). The X-ray-induced luminescence shows an increase with increasing concentrations of Eu2O3 until 0.10%. The samples with the maximum intensity were compared with bismuth germanate oxide (BGO) crystals, which are used as radiation detectors, and were found to be as effective as 33.65% of the BGO crystals. The results demonstrate that the current samples could be a potential candidate for use in scintillator applications.