Concentrated efforts were made towards the synthesis of rare-earth activated inorganic oxides based materials for potential applications like solid state lighting (SSL), displays, sensing device and so on. Materials now used in SSL applications like Ce:YAG (excited by blue LED) and tricolour phosphors (excited by UV LED) have their own drawbacks. In this regard as a complimentary materials, NaGd_1-xDy_x(WO₄)₂  (Dy:NGW)   were prepared in sol-gel methods for possible application in SSL devices. Dy:NGW have two principle emission schemes in blue and yellow region corresponding to transitions of ⁴F_9/2-⁶H_15/2 and ⁴F_9/2-⁶H_13/2 at specific wavelengths, 480 and 574 nm.  Sol-gel synthesised Dy:NGW powders were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), Fourier transform infra-red spectroscopy (FT-IR), Raman and spectroflorimeter analysis. The disordered NGW scheelite structure was confirmed by XRD results. SEM images clearly show the surface morphology and size of particles. The formation of tungstate tetrahedral and its corresponding vibration were analyzed with FT-IR and Raman studies. The combined charge transfer band (CTB) of O^2--W and O^2--Dy³⁺ were obtained in excitation spectrum. The CTB observed in the region of 230 to 310 nm and high absorption centered at 270 nm and above 310 nm ascribe the various f-f transitions of Dy³⁺ ions. Compared to CTB at 270 nm the f-f transition at 353 nm has high absorption intensity as observed in the emission spectrum.  The concentration and excitation wavelength dependent luminescence property were analyzed through emission spectrum. Three lines were observed at 480, 575 and 665 nm in blue, yellow and red region corresponding to the transitions of  ⁴F₉ to⁶H_J (J = 15/2, 13/2 and 11/2) in the emission spectrum.  Based on the results, the optimum dopant concentration of Dy³⁺ ions in NGW has been found to be 7 at% .   

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