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A series of Sr3Gd1−xLi(PO4)3F: xSm3+ (x = 0.02, 0.04, 0.06, 0.08) phosphors were synthesized by a high-temperature solid state method. The Sm3+ activated Sr3GdLi(PO4)3F phosphors can be efficiently excited by the wavelengths in the range from 350 to 450 nm, which matches perfectly with that of the commercial near-UV LED chips. The optimal doping concentration of Sr3Gd1−xLi(PO4)3F: xSm3+ phosphors was determined to be x = 0.04, corresponding to the quantum efficiency of 2.23%, and the CIE chromaticity coordinates (x = 0.5172, y = 0.4641). The concentration quenching mechanism of Sm3+ in Sr3GdLi(PO4)3F host is mainly attributed to the dipole-dipole interaction, which was confirmed by the fluorescent lifetimes. The effect of temperature on the photoluminescence property of Sr3GdLi(PO4)3F: Sm3+ was investigated. 90% of the intensity is preserved at 150 °C. In addition, a white light emitting diode (WLED) lamp was fabricated by a 405 nm n-UV LED chip coated with Sr3Gd0.96Li(PO4)3F:0.04Sm3+ phosphor and commercial yellow phosphor (YAG: Ce3+) of a certain mass ratio. The present work indicates that the Sr3GdLi(PO4)3F: Sm3+ orange-red-emitting phosphors tend to be potential application in n-UV WLED. [ABSTRACT FROM AUTHOR]

Gallium-Indium co-substituted yttrium aluminum garnet (YAG:Yb,Tm) phosphors were synthesized by co-precipitation method. It can be seen that gallium and indium ions co-substitution didn't change the phase of YAG. The upconversion luminescence (UCL) properties of the Gallium-Indium co-substituted (YAG:Yb,Tm) samples were measured under 980 nm excitation. The effects of different Inconcentration on the luminescence properties of Gallium-Indium co-substituted (YAG:Yb,Tm) were also investigated. The fluorescence-lifetime investigation shows that the substitution of Ga and In has a significant influence on energy transfer between Yb and Tm in the YAG samples. [ABSTRACT FROM AUTHOR]