[01] Ravi Shrivastava, Faculty of Science & Technology, ICFAI University, Raipur (CG), India. [02] Manoranjan Dash, Faculty of Science & Technology, ICFAI University, Raipur (CG), India.

In present paper we prepared SrSiO₃ doped with different concentrations of Dy³⁺ ions (0.2, 0.5, 1.0, 1.5 and 2.0mol%) by modified high temperature solid state reaction technique. Sample with optimum Photoluminescence (PL) intensity was characterized by- X-ray diffraction (XRD) Technique. XRD spectrum observed for prepares sample matched quite significantly with Crystallographic open database (COD), card number 96-431-7121. This COD is for monoclinic SrSiO₃ with space group C 1 2/c 1 (15). Photoluminescence studies of all prepared samples were done. Emission spectra exhibited 2 prominent peaks at 473, 576 and 658 nm respectively. Here, Dy³⁺ acts as an activator. A peak centered at 473 nm is due to the transition ⁴F_9/2→⁶H_15/2 (Blue Colour) of Dy³⁺ ions. Similarly, 576 and 658 nm peaks are originated due to transition ⁴F_9/2→⁶H_13/2 (Green Colour) of Dy³⁺ions occupied at different sites. Emission at 660 nm is due to transition ⁴F_9/2→⁶H_11/2 (Red Colour). CIE coordinates expressed that, the overall emission is near white light. In order to investigate the suitability of the samples for white colour light sources for industrial use, Correlated Colour Temperature (CCT). Values of CCT were found, well within the defined acceptable range and emission is considered to be cool in appearance.

Luminescence, White LED, CCT, Dysprosium, Phosphor

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