Enhanced luminescence performance of CaO:Ce3+, Li+, F− phosphor and its phosphor-in-glass based high-power warm LED properties. Issue 15 (22nd March 2018)

• Record Type: Journal Article
• Authors: Deng, Jiankun; Zhang, Haoran; Zhang, Xuejie; Molokeev, Maxim S.; Qiu, Jianbei; Liu, Yingliang; Lei, Bingfu; Ma, Li; Wang, Xiaojun
• Is Part Of: Journal of materials chemistry. Volume 6:Issue 15(2018)
• Page Start: 4077
• Page End: 4086
• Publication Date: 2018-03-22
• Subjects: Materials -- Periodicals; Chemistry, Analytic -- Periodicals; Optical materials -- Research -- Periodicals; Electronics -- Materials -- Research -- Periodicals; 543.0284
• DOI: 10.1039/c8tc00813b
• Languages: English
• ISSNs: 2050-7526

Abstract

Abstract : CaO:Ce 3+, Li +, F − phosphors with improved luminescence performance were fabricated for use in phosphor-in-glass-based high-power warm LEDs. Abstract : To obtain white light-emitted diodes (wLEDs) with a low correlated color temperature (CCT) and a high color rendering index (CRI), red-emission is indispensable in their emission spectra. Herein, CaO:Ce 3+, Li +, F − yellow phosphors with more red spectral component have been prepared via a high temperature solid-state reaction. As compared to the F − undoped samples, CaO:Ce 3+, Li +, F − phosphor have lower critical doping concentration of Ce 3+ and show stronger luminescence. At the critical concentration, a quantum efficiency of 66.4% and enhanced thermal and chemical stability were obtained in CaO:Ce 3+, Li +, F − . Furthermore, a CaO:Ce 3+, Li +, F − -based phosphor-in-glass (PiG) using the red-emitting glass system with the composition of SiO2 –Na2 CO3 –Al2 O3 –CaO:Eu 3+ as the host material was constructed and used for high-power white LED applications. Such PiG samples with different phosphor doping concentrations can satisfy various light color demands and display higher reliability than the CaO:Ce 3+, Li +, F − phosphor. An optimal PiG-based wLED exhibits color coordinates of (0.3769, 0.3386), a CCT of 3774 K, a CRI of 82.5 and a LE of 73.1 when the mass ratio of phosphor to glass matrix was 7 : 50 in PiG. Moreover, such PiG-based wLED also showed acceptable color stability under different drive currents. All the above results demonstrate that CaO:Ce 3+, Li +, F − can be expected to be a potential alternative yellow phosphor for blue light excited PiG based warm wLEDs, particularly for high-power devices.