Reflective laser drive converter with Al2O3 particles based on high thermal conductivity AlN substrate: achieving high power density light illumination

To address the thermal management challenge in phosphor-in-glass (PiG) materials for laser lighting due to low glass matrix thermal conductivity, this study developed YAG:Ce 3+ -Al 2 O 3 PiG composites reinforced with Al 2 O 3 particles, achieving a thermal conductivity of 78.6 W/(m·K). A TiO 2 reflective layer optimized for reflection and light conversion was introduced between the AlN substrate and PiG layer. Systematic optimization of Al 2 O 3 content and preparation conditions yielded YAG:Ce 3+ -Al 2 O 3 PiG composites with exceptional performance: maximum luminous flux (LF) of 2515 lm under blue laser excitation, saturation threshold (ST) of 27.57 W/mm 2 , and luminous efficiency (LE) of 174.7 lm/W. LF and ST increased by 184.5 % and 167.4 %, respectively, compared to non-Al 2 O 3 counterparts. The surface temperature of 9 wt% Al 2 O 3 PiG reached 363.85 K, 34.4 % lower than the working temperature of the sample without Al 2 O 3 addition. Stable light emission and high photothermal stability confirm its potential as a high-brightness laser lighting material.