Color Tunable Composite Phosphor Ceramics Based on SrAlSiN3:Eu2+/Lu3Al5O12:Ce3+ for High-Power and High-Color-Rendering-Index White LEDs/LDs Lighting

• Published in: Materials Vol. 16; no. 17; p. 6007
• Main Authors: Ye, Shenrui, Li, Yukun, Qiang, Ming, Lou, Wenhui, Dai, Bo, Lin, Hui, Han, Zhaoxia, Hong, Ruijin, Zhang, Dawei
• Format: Journal Article
• Language: English
• Published: Basel MDPI AG 31-08-2023; MDPI
• Subjects: bi-layer composite phosphor; Ceramics; Cerium; Color temperature; Energy consumption; Europium; Heat conductivity; Light emitting diodes; Lighting; Low temperature; low-temperature sintering; Lu3Al5O12:Ce phosphor ceramics; Materials selection; Optical properties; Phosphors; Rendering; Semiconductor lasers; Silicones; Sintering; SrAlSiN3:Eu2+-PiG; Temperature; Test systems; Vacuum sintering
• ISSN: 1996-1944; 1996-1944
• DOI: 10.3390/ma16176007

Lu3Al5O12:Ce3+ phosphor ceramics were fabricated by vacuum sintering. On this basis, a bi-layer composite phosphor was prepared by low-temperature sintering to cover the phosphor ceramics with a layer of SrAlSiN3:Eu2+-phosphor-in-glass (PiG). The optical, thermal, and colorimetric properties of LuAG:Ce3+ phosphor ceramics, SrAlSiN3:Eu2+ phosphors and SrAlSiN3:Eu2+-PiG were studied individually. Combining the bi-layer composite phosphors with the blue LED chip, it is found that the spectrum can be adjusted by varying the doping concentration of SrAlSiN3:Eu2+-PiG and the thickness of Lu3Al5O12:Ce3+ phosphor ceramics. The maximal color rendering index value of the white LED is 86, and the R9 is 61. Under the excitation of a laser diode, the maximum phosphor conversion efficacy of the bi-layer composite phosphors is 120 lm/W, the Ra is 83, and the correlated color temperature is 4534 K. These results show that the bi-layer composite phosphor ceramic is a candidate material to achieve high color rendering index for high brightness lighting.