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The luminescent properties of europium (Eu)- and dysprosium (Dy)-co-doped K3 Ca2 (SO4 )3 Cl halosulfate phosphors were analyzed. This paper reports the photoluminescence (PL) properties of K3 Ca2 (SO4 )3 Cl microphosphor doped with Eu and Dy and synthesized using a cost-effective wet chemical method. The phosphors were characterized by X-ray diffraction and scanning electron microscopy. The CIE coordinates were calculated to display the color of the phosphor. PL emission of the prepared samples show peaks at 484 nm (blue), 575 nm (yellow), 594 nm (orange) and 617 nm (red). The emission color of the Eu,Dy-co-doped K3 Ca2 (SO4 )3 Cl halophosphor depends on the doping concentration and excitation wavelength. The addition of Eu in K3 Ca2 (SO4 )3 Cl:Dy greatly enhances the intensity of the blue and yellow peaks, which corresponds to the (4)  F9/2  → (6) H15/2 and (4)  F9/2  → (6) H13/2 transitions of Dy(3+) ions (under 351 nm excitation). The Eu(3+) /Dy(3+) co-doping also produces white light emission for 1 mol% of Eu(3+) , 1 mol% of Dy(3+) in the K3 Ca2 (SO4 )3 Cl lattice under 396 nm excitation, for which the calculated chromaticity coordinates are (0.35, 0.31). Thus, K3 Ca2 (SO4 )3 Cl co-doped with Eu/Dy is a suitable candidate for NUV based white light-emitting phosphors technology.

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In this study, we are successfully synthesized terbium and samarium (Tb3+/Sm3+) doped K3Ca2(SO4)3Cl phosphors by wet chemical method, and synthesized phosphors were characterized by XRD, SEM, and Photoluminescence (PL) techniques, and studied in detail. Photoluminescence analysis, we can see that under the Near-UV (NUV) excitation of 380nm, the Tb3+ activated samples showed a prominent green emission peak at 546nm attributed to the 5D4→7F5 transition of Tb3+ions. While the PL emission spectra of 404 nm light excited K3Ca2(SO4)3Cl:Sm3+phosphorshowedthree emission lines at 565nm, 598nm and 645nm attributed to 4G5/2→6H5/2, 4G5/2→6H7/2, and4G5/2→6H9/2 transitions of Sm3+ ions, respectively. The CIE coordinates were calculated to be (0.263, 0.515) for K3Ca2(SO4)3Cl:Tb3+and (0.532, 0.462) for K3Ca2(SO4)3Cl: 1.5mol%Sm3+, which liedin the green and orange regions, respectively. The entire photoluminescence results indicated that phosphor K3Ca2(SO4)3Cl doped with Tb3+ and Sm 3+may turn out to be an important component of pc-white LEDs and display devices.

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