High-performance Al2O3–Ce:YAG ceramics for white LED and LD by the optimization of Ce3+ concentration

Abstract

Al 2 O 3 –Ce:YAG composite ceramics are widely used in high-power white light-emitting diodes (LED) and laser diode (LD), because of their good optical performance and high luminous efficiency, particularly, excellent thermal conductivity. In this study, we prepared Al 2 O 3 –Ce:YAG composite ceramics doped with different concentrations of Ce 3+ by vacuum sintering technique. The emission peak of Ce 3+ is redshifted from 533 nm to 553 nm with the increase of Ce 3+ concentration from 0.1 at% to 1.5 at%. When excited by a blue LED with 455 nm, the luminous efficiency of the ceramic doped with 1.2 at% Ce 3+ reached 106 lm/W and a low correlated color temperature of 3600 K was achieved. Moreover, when excited by the 450 nm blue LD with 5.8 W of electrical power, a higher luminous efficiency of 171 lm/W was obtained with 0.5 at% Ce 3+ doped. These results indicate that Al 2 O 3 –Ce:YAG composite ceramics doped with Ce 3+ concentrations of 1.2 at% exhibit excellent optical properties and are promising phosphor-convert materials for white LED and LD lighting applications. • Al 2 O 3 –Ce:YAG composite ceramic phosphors with different Ce 3+ concentration have been fabricated . • The emission peaks are redshifted from 533 nm to 553 nm with the increase of Ce 3+ concentration from 0.1 at% to 1.5 at%. • When the Ce 3+ concentration was 1.2 at%, the composite ceramic reached the highest luminous efficiency of 106.45 lm/W. • The optical properties of the composite ceramics were also tested when installed on LD.