Al2O3–Ce:YAG composite phosphor ceramics for white laser lighting: Novel preparation and regulatable properties

• Published in: Journal of the American Ceramic Society Vol. 106; no. 10; pp. 5933 - 5943
• Main Authors: Wang, Yanbin, Huang, Xinyou, Cheng, Ziqiu, Hu, Dianjun, Zhu, Danyang, Chen, Penghui, Tian, Feng, Yuan, Qiang, Kosyanov, Denis Yu, Li, Jiang
• Format: Journal Article
• Language: English
• Published: Columbus Wiley Subscription Services, Inc 01.10.2023
• Subjects: Aluminum oxide; Ceramics; Cerium; Color temperature; composite phosphor ceramics; composition uniformity; coprecipitation method; Grain size; Lasers; Lighting; luminescence properties; Optimization; Phases; Phosphors; Semiconductor lasers; Sintering (powder metallurgy); solid‐state laser lighting; Vacuum sintering; White light; YAG lasers
• ISSN: 0002-7820; 1551-2916
• DOI: 10.1111/jace.19238

In this work, a series of Al2O3–Ce:YAG phosphor powders were synthesized by regulating the excess Al3+ of (Y,Ce)3Al5O12 via coprecipitation method for the first time, where Al3+, Ce3+, and Y3+ elements were uniformly distributed. With the increase of Al3+ content, the morphology of the powders changed from wormlike shapes to flaky shapes, and Y3Al5O12 phases had a tendency to convert to YAlO3 phases. The x wt.% Al2O3–(Y0.999Ce0.001)3Al5O12 (x = 20, 30, 40, 50, 60, and 70) composite phosphor ceramics (CPCs) were obtained by vacuum sintering (1775°C × 10 h), where Al2O3 and Ce:YAG phases were also well‐distributed. When the Al2O3 content was 30–40 wt.%, the average grain size of Al2O3 was close to that of Ce:YAG. A solid‐state laser lighting device was constructed by a 450 nm laser source and CPCs in a reflection mode. By adjusting the laser power, the correlated color temperature (CCT) values of white laser diodes (LDs) were achieved close to the standard white light of 6500 K. Impressively, the white LDs equipped with the 40 wt.% Al2O3‐containing CPCs showed the optimum CCT of 6498 K (color coordinates: 0.31 and 0.38), as well as a high luminous flux of 1169 lm and efficiency of 166 lm/W at the LD power of 7.05 W. This work has provided a potential idea to optimize the composition uniformity of Al2O3–Ce:YAG CPCs as also to explore their excellent performance in the application of white laser lighting.