YAG:Ce³⁺ Transparent Ceramic Phosphors Brighten the Next-Generation Laser-Driven Lighting

Y₃ Al₅ O₁₂ :Ce³⁺ (YAG:Ce³⁺ ) transparent ceramic phosphors (TCPs) are regarded as the most promising luminescent converter for laser-driven (LD) lighting. High-quality YAG:Ce³⁺ TCPs are still urgent for high efficiency LD lighting devices. YAG:Ce³⁺ TCPs in a vacuum ambience by using nano-sized raw materials are prepared. Controlling defects by adding nano-sized MgO and SiO₂ simultaneously enables a high transmittance nearly 80%. After annealing in air furthermore, the luminous efficiency is enhanced greatly from 106 to 223 lm W^-1 , which is the best result reported now for LD lighting. These results demonstrate that the optimizing YAG:Ce³⁺ TCPs in a fitting strategy will brighten once again in the next-generation LD lighting. Based on scanning electron microscopy (SEM) coupled with a cathodoluminescence system, defects and Ce³⁺ distributions in grains are identified directly for the first time.