Ca₈Mg₇Si₉N₂₂:Ce³⁺—A Yellow-Emitting Nitride Phosphor for White Light Emitting Diodes

Abstract

Nitridomagnesosilicate phosphors are promising candidates for white light emitting diodes. Here, we report a yellow nitride phosphor Ca 8 Mg 7 Si 9 N 22 :Ce 3+ , which exhibits a broad band emission in the spectral range of 475−675 nm under the excitation of 445 nm. The photoluminescence intensity of Ca 8−x Mg 7 Si 9 N 22 :xCe 3+ (0.01 ≤ x ≤ 0.11) reaches a maximum when x = 0.05. CIE coordinates and the color purity of Ca 7.95 Mg 7 Si 9 N 22 :0.05Ce 3+ are (0.449, 0.531) and 84.0%, respectively. The Ca 7.95 Mg 7 Si 9 N 22 :0.05Ce 3+ phosphor exhibits a good color drifting resistance with a maximum chromaticity shift of 0.0085 at 475 K. By combining the as-synthesized yellow nitride phosphor Ca 7.95 Mg 7 Si 9 N 22 :0.05Ce 3+ and red nitride phosphor SrLiAl 3 N 4 :Eu 2+ with a commercial blue InGaN chip, an all-nitride white light emitting diode device is fabricated, and a warm white light is generated with chromatic coordinates (0.471, 0.364) and color temperature of 2194 K.

A broadband yellow Yb2+-doped oxynitride phosphor for high-performance white light-emitting diodes

“…5,8 Over the past two decades, many efforts have been made to develop broadband yellow phosphors, such as (La,Ca)Si 6 N 11 :Ce 3+ (FWHM: 130-143 nm, 3960-4247 cm −1 ), Ca 8 Mg 7 Si 9 N 22 :Ce 3+ (FWHM: ∼132 nm, ∼4127cm −1 ), La 3 BaSi 5 N 9 O 2 :Ce 3+ (FWHM: 167 nm, 4700 cm −1 ), Ca-α-SiAlON:Eu 2+ (FWHM: 95 nm, 2700 cm −1 ), and BaAl 2 O 4 :Eu 2+ (FWHM: ∼130 nm, 3767 cm −1 ). 4,6,[9][10][11] Similar to Ce 3+ and Eu 2+ , luminescent materials activated by Yb 2+ also exhibit broadband and tuneable emissions due to the 5d-4f transition. [12][13][14] Xie et al first reported Yb 2+ -doped oxynitride phosphors (M-α-SiAlON:Yb 2+ , M = Ca, Mg, Li, and Y), which exhibit bright green emission (λ em = 549 nm).…”

High-performance ultra-narrow-band green-emitting phosphor LaMgAl11O19:Mn2+ for wide color-gamut WLED backlight displays

“…3e), which are much better than that of other reported phosphors. 33–36 The results indicate that the LMAO:0.28Mn 2+ phosphor exhibits an excellent resistance to temperature-dependent color drifting. The luminescence lifetimes of the phosphors usually shorten when temperature-dependent quenching occurs due to an additional nonradiative contribution to the decay process.…”

Efficient Broadband Yellow-Green Emission of Vacancy Halide Double Perovskites Through the Ion-Exchanged Strategy

“…Compared to traditional incandescent lamps, phosphor-converted white LEDs (pc-WLEDs) are extensively studied due to their long working time, environmental friendliness, and energy saving nature. − In the current development of WLEDs, there are two types that have attracted much attention. − In short, they are composed of the yellow phosphor plus a blue chip (WLED1) − and a mixture of multiple colors plus an ultraviolet chip (WLED2). − ,, With the advancement of research, yellow phosphor plays an important role in WLEDs. − It should be pointed out that yellow phosphors that have both ultraviolet and blue excitation ranges are relatively rare. , The main advantage of this phosphor is that it can not only combine with blue LED chips to form another WLED1 but also mix other color phosphors with UV chips to form WLED2. In addition, unlike the narrow-band emission of rare earth ions, − the broadband emission of this yellow phosphor is more suitable for current mainstream pc-WLEDs.…”