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Investigation of photoluminescence properties, quenching mechanism and thermal stability of the red-emitting phosphor based on Eu ions doped apatite host NaLa9(SiO4)6O2

A series of Eu ions doped apatite structure NaLa9(1-x)Eu9x(SiO4)6O2 phosphors were successfully synthesized by solid state reaction. The phase structure and luminescence properties morphology of the NaLa9(1−x)Eu9x(SiO4)6O2 phosphors were systemically investigated. The results indicate that all the samples adopt NaLa9(SiO4)6O2 phase and can be effectively excited by UV light or blue light to realize an intense red emission (615 nm). The quenching concentration for the transition of 5D0 → 7F2 in the NaLa9(1−x)Eu9x(SiO4)6O2 phosphor reaches up x = 0.7. The theoretical quenching concentration, quenching mechanism and thermal stability were also discussed. The as-prepared phosphors can compensate for the deficiency of the red emitting region of YAG:Ce3+ phosphor. The results show that NaLa9(1−x)Eu9x(SiO4)6O2 phosphor has potential application in solid state lighting.