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Sr x Ca 1−x AlSiN 3 : Eu 2+ phosphors were prepared by using the high temperature solid state reaction in a 1.1 Mpa N 2 atmosphere. The phase structures, photoluminescence (PL) properties, and chromaticity properties of the phosphors affected by Sr/Ca Substitution have been investigated in detail. With increasing Sr content (x value), the crystal grain became bigger and the average grain size increased from 5 µm to 10 µm. PL emission bands of Sr x Ca 1−x AlSiN 3 : Eu 2+ showed a blue-shift from 660 (x=0) to 617 nm (x=0.8), the shoulder of the excitation spectra around 550 nm showed a slightly blue-shift and decay lifetime shortened from 776.96 (x=0.2) to 642.35 ns (x=0.8). Both the emission and excitation intensity of peak position increased with Sr content increased. The ideal white light with high CRI (Ra>88) can be obtained by mixing the Sr x Ca 1−x AlSiN 3 : Eu 2+ phosphors and commercial green phosphors with appropriate proportion of the components.

BaxSr2−xSiO4:0.02Eu2+ (x = 0, 0.2, 0.5, 0.8, 1, 1.5 and 2) phosphors were synthesized by high temperature solid-state reaction. The effect of Ba2+ doping on the thermal stability and reliability properties of the phosphors were investigated. The photoluminescence (PL) emission bands of BaxSr2−xSiO4:0.02Eu2+ showed blue shift from 576 to 508 nm with increasing Ba content under excited at 460 nm. As x value is more than 1, the thermal stability of BaxSr2−xSiO4:0.02Eu2+ phosphor is decreased significantly. As the temperature increases from 300 to 500 K, PL intensity of BaxSr2−xSiO4:0.02Eu2+ phosphor decreases by 91.32, 80.26, 64.80, 69.91 and 94.12 % of the initial PL intensity for x = 0, 0.5, 1, 1.5 and 2, respectively. The thermal cycling testing results show that the relative PL intensity of BaxSr2−xSiO4:0.02Eu2+ phosphor decrease to 84.08, 85.99, 90.18, 92.59, 94.89, 90.88 and 85.42 % with x value is 0, 0.2, 0.5, 0.8, 1, 1.5 and 2 after storing the phosphors into an ambient condition of 120 °C for 1 h and −40 °C for 1 h by turns for five times. Reliability test results show that the relative PL intensity of BaxSr2−xSiO4:0.02Eu2+ phosphor decrease to 83.90, 92.36, 93.88, 95.89, 95.85, 93.47 and 85.03 % with x value is 0, 0.2, 0.5, 0.8, 1, 1.5 and 2 after the ambient condition of 85 °C/RH 85 % for the exposure time of 168 h; The relative PL intensity of BaxSr2−xSiO4:0.02Eu2+ phosphor decrease to 75.23, 83.63, 85.76, 89.58, 88.28, 85.03 and 70.97 % with x value is 0, 0.2, 0.5, 0.8, 1, 1.5 and 2 after soaking into boiled water for 3 h. It can be summarized that the addition of Ba with the x value less than 1 could increase the thermal stability largely and enhance the reliability of BaxSr2−xSiO4:0.02Eu2+ phosphors remarkably.

Y3Al5−xGaxO12:0.05Ce3+ (x = 0–2) phosphors have been prepared by using the high temperature solid state reaction in a reducing H2 atmosphere. The phase structures, photoluminescence (PL) properties, and chromaticity properties of the phosphors have been investigated in detail. SEM image shows the phosphors exhibits well-developed crystal faces with the crystal size is about 50 μm. The two PLE excitation bands attributed to the 4f–5d 1 and 4f–5d 2 transitions showed shift in opposite directions as x increasing. PL emission bands of Y3Al5−xGaxO12:0.05Ce3+ showed a blue-shift tendency gradually from 560 to 520 nm with increasing Ga content (x value). The PL measurement combined with blue light and CIE chromaticity diagram show that ideal white light with high CRI can be obtained by mixing the Y2.95Al3.5Ga1.5O12:0.05Ce (or Y2.95Al3Ga2O12:0.05Ce) phosphors and commercial red phosphors with appropriate proportion of the components.