Combustion synthesis and photoluminescence of Ca2SrWO6: perovskite: An approach for white light emission Dy3+ double

Luminescent Ca2SrWO6:Dy3+ double perovskites are synthesized via the combustion route of material synthesis, wherein urea is taken as fuel. The as-prepared phosphor series comprehensively characterized for their structural and photoluminescence (PL) properties. The Rietveld refinement of XRD data revealed monoclinic crystallized microcrystals with mixed particles of the size of less than 1 mu m, studied via SEM. Ca2SrWO6:Dy3+ displayed standard Dy3+ transitions F-4(9/2)-H-6(15/2) (blue emission) and F-4(9/2)-H-6(13/2) (yellow emission) collectively resulted in white light emission, confirmed via CIE study. Under 278 and 388 excitations, 2 mol% doping of Dy3+ found to be optimum concentration, beyond which concentration quenching is observed due to dipole-dipole interaction. The Y/B ratio similar to 1 shows potential to produce white light and make phosphor suitable for WLED applications. The Ca2SrWO6:Dy3+ phosphor displayed notably high thermal stability with PL intensity persisted 77.6 % at LED burning temperature (150 degrees C) when compared to PL intensity attained at room-temperature, which is basically due to the rigid perovskite structure. In addition, the PL decay lifetime of F-4(9/2) state was calculated by utilizing decay curves. Subsequently, the PL quantum efficiency and non-radiative relaxation rate are determined. The theoretical model of Auzel's fit function is used to calculate to quantum efficiency and was found to be 93.27 % for Ca2SrWO6:2 % Dy3+ phosphor. Moreover, the photometric results reveals that the CIE points are lies in white region of CIE diagram with comparable CCT. The collective results indicated the utility of the phosphor for potential WLED applications.