Selective coordination of N3− and tuning of luminescence in garnet (Y1−x,Lax)3(Al,Si)5(O,N)12: Ce3+ phosphors

Spectrum deficiency in red component of YAG: Ce3+ phosphor is hopeful to be made up by small amount of Si4+-N3− replacing Al3+-O2− for high quality lighting, while the important indicators of emission efficiency and thermal quenching properties dramatically decrease in this approach. Thus micro-structural tuning by cation substitution usually is an effective way to improve the luminescence properties. This study focuses on the structural variations and tuning luminescence induced by La3+ incorporating into Y3(Al,Si)5(O,N)12: Ce3+ phosphors. The results show that the emission efficiency and thermal quenching properties are remarkably enhanced, while the spectrum shows blue-shift to some extent. The mechanism of property variation is clarified, which is ascribed to selective coordination of N3−. This effect is important and possible to be extended to other N3− contained garnet phosphors, becoming an important rule for materials design. The obtained phosphors are promising to develop into practicable phosphors for high color rendition w-LEDs.