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Title: Dual-site occupancy induced broadband cyan emission in Ba 2 CaB 2 Si 4 O 14 :Ce 3+
There is a significant need to identify cyan-emitting phosphors capable of filling the “cyan-gap” (480–520 nm) in full-visible-spectrum phosphor-converted white light-emitting diodes (pc-wLEDs). Here, a new broadband cyan-emitting phosphor that enables addressing of this challenge is reported. The compound, Ba 2 CaB 2 Si 4 O 14 :Ce 3+ , presents a bright cyan emission peaking at 478 nm with a large full width at half maximum of 142 nm (6053 cm −1 ), and minimal thermal quenching. The photoluminescence properties originate from Ce 3+ residing at two different crystallographic sites, a [BaO 9 ] distorted elongated square pyramid and a [CaO 6 ] trigonal prism. This combination results in an efficient, broad emission covering the blue to green region of the visible spectrum. Fabricating a simple dichromatic ultraviolet ( λ ex = 370 nm) pumped pc-wLED using Ba 2 CaB 2 Si 4 O 14 :Ce 3+ along with a commercially available red phosphor demonstrates full-visible-spectrum white light with high color rendering index ( R a > 90) and tunable correlated color temperature, showing the potential of this material for achieving high-quality LED-based lighting.
Authors:
; ; ; ;
Award ID(s):
1847701 1911311
Publication Date:
NSF-PAR ID:
10206140
Journal Name:
Journal of Materials Chemistry C
Volume:
8
Issue:
44
Page Range or eLocation-ID:
15626 to 15633
ISSN:
2050-7526
Sponsoring Org:
National Science Foundation
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