Ba1-y Sry La2-x Dyx ZnO 5 (x=0.01-0.2, y=0-0.65) phosphors were prepared by a solid-state reaction, and their photoluminescence properties were investigated for the conversion of the UV light emitting diode radiation to white light. The results showed that the maximum emission intensity of the samples without Sr 2+ substitution was achieved at the Dy3+ doping level x=0.07 under the UV excitation at 388 nm, and the Commission Internationale del'Eclairage (CIE) chromaticity coordinate of the total emissions was located at (0.256, 0.334). When substituted by Sr2+, the X-ray diffraction showed that the lattice constants and unit cell volumes of Ba1-y Sry La1.93 Dy0.07 ZnO5 (y=0-0.65) decreased linearly with the increasing Sr2+ content. The color tone of the Ba1-y Sry La1.93 Dy0.07 ZnO5 phosphors could be tuned by the amount of Sr2+ substitution as the consequence of the induced lattice distortion, which resulted in a change in the local site symmetry around the Dy3+ ions. The CIE chromaticity coordinate (x,y) of Ba1-y Sry La1.93 Dy0.07 ZnO5 phosphors varied from bluish white (0.256, 0.334) at y=0 to near white (0.315, 0.370) at y=0.65 under the UV excitation at 388 nm.
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