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Y1.94MAl4SiO12:0.06Ce3+ (M = Ba, Sr, Ca, Mg) phosphors were successfully prepared through a classic solid‐state reaction method. The crystal structures, photoluminescence spectra, quantum yields, and thermal stabilities of the phosphors were investigated in detail. The results indicate that all Y1.94MAl4SiO12:0.06Ce3+ phosphors maintain the crystal structure of garnets. The emission peaks of Y1.94MAl4SiO12:0.06Ce3+ (M = Ba, Sr, Ca, Mg) phosphors are located at 537, 538, 554, and 565 nm, respectively. A red‐shift trend of emission peak is observed with decreasing M radius, which can be ascribed to the increase in the crystal‐field splitting in the Ce3+ 5d level owing to the co‐doping of M2+−Si4+. Under 460 nm excitation, the luminescence quantum yields and thermal stabilities of the Y1.94MAl4SiO12:0.06Ce3+ phosphors decreased with the decrease of M radius. The IQE of the Y1.94BaAl4SiO12:0.06Ce3+ phosphor is 92.89%, and the resistance to thermal quenching is improved to be 93.32% at 150°C. In addition, the color shifts of Y1.94MAl4SiO12: 0.06Ce3+ phosphors with increasing temperature are all tiny, which also demonstrates good resistance to thermal quenching of luminescence. The linear shrinkage of Y1.94MAl4SiO12:0.06Ce3+ phosphors is significantly improved compared with that of YAG: Ce3+, which is expected to generate Y1.94MAl4SiO12:0.06Ce3+ transparent/translucent ceramics and fabricate high‐powder w‐LEDs for high‐quality solid‐state lighting in the future. [ABSTRACT FROM AUTHOR]

Current white light emitting diodes (WLEDs) have poor thermal stability and lack red‐light, which restrict their applications in high‐power and high‐color‐rendering‐index solid‐state lighting. YAG glass‐ceramics provide an efficient way to resolve these problems. Herein, novel YAG‐embedded calcium bismuth borate glass‐ceramics (YAG‐GCs) with Eu3+ doping were prepared using a rapid melt quenching technique. The precursor glass exhibits superior YAG refractive index matching and high transmittance. Differential scanning calorimeter simulations verify YAG particles react with the precursor glass. The degree of YAG erosion is slight but monotonously increases with the co‐sintering temperature from 640 to 700°C. The erosion products probably contain YAB (Al3Y(BO3)4), Al3Eu(BO3)4, Bi24B2O39, and Ca12Al14O33 phases, and the Bi ion valence state is maintained during the reaction process. The energy transfer from Ce3+ to Eu3+ is suppressed. The YAG‐GC PL intensities monotonously increase as the co‐sintering temperature decrease from 640 to 700°C and the YAG content increase from 2.5 to 7 wt.%. The optical parameters of a WLEDs packed by YAG‐GCs and blue chips are a luminous efficiency of 105.3 lm/W, correlated color temperature of 3940 K and color rendering index of 70.1. The as‐prepared YAG‐GCs are promising candidates for high‐power, warm WLEDs due to their superior thermal stability, high quantum efficiency, and low cost. [ABSTRACT FROM AUTHOR]