Studies on white light emission of Sr2MgSi2O7 doped with Dy3+ phosphors

Present paper reports the preparation of Sr2MgSi2O7 doped with Dy3+ ions by modified high temperature solid state reaction technique. Samples were prepared for different concentration of Dy3+ (0.5, 1.0, 1.5, 2.0 and 2.5 mol%). Sample with optimum photoluminescence intensity was characterized by X-ray diffraction (XRD) technique. Observed XRD spectrum matched with crystallographic open database card specifically appeared for Sr2MgSi2O7 phosphor. This is a confirmation of proper preparation of the sample. Photoluminescence studies of these samples were done. Emission spectra exhibited 5 prominent peaks at 480, 490, 575, 590 and 660 nm respectively. In this case Dy3+ acts as an activator. Peaks centered at 480 and 490 nm are due to the transition F-4(9/2) -> H-6(15/2) (blue color) of Dy3+ ions occupied at different sites. Similarly 575 and 590 nm peaks are originated due to transition F-4(9/2) -> H-6(13/2) (yellow-orange color) of Dy3+ ions occupied at different sites. Emission at 660 nm is due to transition F-4(9/2) -> H-6(11/2) (red color). CIE coordinates have been calculated for each sample and its value exhibited that, overall emission is near white light. In order to investigate the suitability of the samples as white color light sources for industrial uses, correlated color temperature (CCT) and color rendering index (CRI) were calculated. Values of CCT and CRI were found, well within the defined acceptable range. (C) 2015 Elsevier Ltd. All rights reserved.