Obtain full visible spectrum light-emitting diode illumination via bismuth-activated cyan phosphors. (March 2022)

• Record Type: Journal Article
• Authors: Wu, S.; Fu, Y.; Liu, Q.; Xiong, P.; Wang, D.; Zhang, G.; Yuan, S.; Chen, Y.
• Is Part Of: Materials today chemistry. Volume 23(2022)
• Publication Date: 2022-03
• Subjects: WLED -- SrLaGaO4:Bi3+ -- Cyan-emitting -- Full-spectrum white lighting; Chemistry -- Periodicals; Materials -- Research -- Periodicals; Materials science -- Periodicals; Chemistry; Materials -- Research; Electronic journals; Periodicals; 660.282
• DOI: 10.1016/j.mtchem.2021.100754
• Languages: English
• ISSNs: 2468-5194

Abstract

Abstract: Developing highly efficient cyan-emitting fluorescent materials is essential to bridge the cyan gap in phosphor-converted white light-emitting diodes for full-spectrum white illumination. Here, a Bi-doped cyan phosphor has been reported to solve this gap. The phase purity, photoluminescence emission/excitation spectra, concentration quenching, lifetime decay curves, and temperature-dependent photoluminescence emission spectra were systematically investigated. SrLaGaO4 :Bi 3+ exhibits a broad excitation band (250–400 nm), which matches with the emission of a commercial near-ultraviolet light-emitting diode chip. The cyan light peaked at 475 nm is observed, which is attributed to the 3 P1 → 1 S0 transition of Bi 3+ . The thermal quenching experiment was performed, and the activation energy was calculated as 0.36 eV. Finally, full-spectrum white light-emitting diode devices were fabricated using SrLaGaO4 :Bi 3+ phosphors, commercial blue BaMgAl10 O17 :Eu 2+ phosphor, green (Ba, Sr)2 SiO4 :Eu 2+ phosphor, and red CaAlSiN3 :Eu 2+ phosphor, which displayed an International Commission on an illumination coordinate of (0.3732, 0.3850), a correlated color temperature of 4290 K, and a color rendering index of 93.2 at a drive current of 20 mA. This result indicates that SrLaGaO4 :Bi 3+ plays an essential role in bridging the cyan gap, providing new inspiration for applying cyan-emitting phosphors in full-spectrum white lighting. Graphical abstract: Bismuth-activated cyan-emitting phosphor SrLaGaO4 : Bi 3+ for near-ultraviolet full visible spectrum light-emitting diode (LED) illumination. Image 1 Highlights: Bi 3+ -doped SrLaGaO4 cyan-emitting light-emitting diode (LED) phosphor was first synthesized. The broad excitation from 250 to 400 nm suitably matches the absorption band of a near-ultraviolet LED chip. SrLaGaO4 :Bi 3+ can be used to fill the cyan gap between the blue and green bands to achieve full-spectral emission. SrLaGaO4 :Bi 3+ phosphor can make white LED devices obtain a higher color rendering index (Ra = 93.2).