A broadband yellow-emitting nitridoalumosilicate Ca4SiAl3N7:Ce3+ phosphor for solid-state lighting

Developing an efficient broadband yellow phosphor with more red-light components and small thermal quenching is of great significance for solid-state lighting. In this study, a broadband yellow-emitting nitridoalumosilicate Ca4SiAl3N7:Ce3+ phosphor was successfully synthesized by a solid-phase method at comparatively low temperature (1350 °C) and normal pressure. The crystal structure and electronic structure of Ca4SiAl3N7 were studied using Rietveld refinement and density functional theory. The photoluminescence properties of the Ca4SiAl3N7:Ce3+ phosphor were studied, including excitation and emission spectra, time-resolved photoluminescence spectra and temperature-dependent emission spectra. The results show that the Ca4SiAl3N7:Ce3+ phosphor can be effectively excited by the blue chip and emit a strong broadband yellow light with maximum at 568 nm and the half width of 142 nm. Moreover, the Ca4SiAl3N7:Ce3+ phosphor exhibits good thermal stability, which can still maintain 75% and 68% of the strength at room temperature when at 150 °C and 200 °C, respectively, and without spectral shift. A warm WLED can be realized by combining Ca4SiAl3N7:Ce3+ yellow phosphor and blue LED chip. This study provides insights into developing novel broadband yellow nitridoalumosilicate phosphor with more red-light components, small thermal quenching and simple synthesis conditions.