Pore-existing Lu3Al5O12:Ce ceramic phosphor: An efficient green color converter for laser light source

Lu3Al5O12:Ce (LuAG:Ce) ceramic - a super-duper green color converter was fabricated by a solid-state reaction method under vacuum. The sintering temperature was adjusted to control the pore characteristics, which would cause different degrees of scattering. Microstructures of ceramics sintered at different temperatures were observed by scanning electronic microscopy (SEM). Photoluminescence (PL) of the ceramics was characterized by a fluorescent spectrophotometer. It was found that the micro-sized pores inside the ceramics play a key role in optimizing the PL intensity. Under the blue laser (450 nm) excitation, the optimized sample with a porosity of 2.88% showed high luminous efficiency of over 200 lm/W and high thermal stability of luminescence. The light conversion efficiency was 50.2% and 44.4% in the dynamic and static mode, respectively. The results highlighted that the prepared ceramics had great potentials for application in solid state laser light source (LLS).