Elaboration of Ce:(Lu,Gd)3Al5O12-Al2O3 transparent nanoceramics through full glass crystallization for high-power warm white LED/LD lighting

Transparent Ce:Lu3Al5O12 (Ce:LuAG) phosphor ceramics are promising for high-power white lighting due to their high quantum efficiency, thermal stability and low thermal quenching. However, the shortage of red spectral composition and expensive price are preventing the application of Ce:LuAG phosphor ceramics in high-quality white lighting. In this work, (Lu,Gd)3Al5O12-Al2O3 (LuGAG-Al2O3) nanoceramics were prepared by partially replacing Lu3+ with Gd3+ through glass crystallization. These ceramics exhibit outstanding transparency and excellent mechanical properties. Compared with Ce:LuAG-Al2O3 transparent nanoceramics, the emission spectrum of transparent Ce:LuGAG-Al2O3 nanoceramics shows a substantial red shift (505 nm→570 nm), which effectively supplement the red light lacking in Ce:LuAG ceramics. With a maximum quantum efficiency of 81.4% and excellent thermal stability (87.6% @423 K), these nanoceramics have potential for high-power white lighting. When used in high-power LED and LD lighting, Ce:LuGAG-Al2O3 transparent nanoceramics achieve continuous adjustable changes from green light to orange-yellow light, and furthermore provide high quality warm white lighting with low color temperature, high color rendering index, and excellent luminous efficiency. Combining the facile and moderate elaboration process through full glass crystallization, the transparent Ce:LuGAG-Al2O3 nanoceramics reported in this paper are therefore regarded as promising color converters candidates for high-power warm white LED/LD lighting.