A novel cyan-emitting phosphor KScSrSi_2−yGe_yO₇:0.07Bi³⁺ for white LEDs with high color rendering index and low correlated color temperature

Abstract

To make up for the cyan gap (480-520nm) in traditional tricolor (blue, green and red) phosphor-converted white light-emitting diodes (LEDs), it is highly important to find efficient cyan phosphors with...

Achieving efficient violet-light-excited blue phosphors by nitridation for violet-chip-based full-spectrum lighting

“…10,11 The WLEDs based on n-UV chips have the advantage of good spectral continuity without a gap. 12,13 However, human eyes feature low perception to UV light and UV light is harmful to the human body. 14,15 Compared with n-UV chips, violet chips can meet the requirements of full-spectrum WLED fabrication, and the external efficiency of violet chips is about 80%, higher than that of 365 nm n-UV chips (44%).…”

Enhancing External Quantum Efficiency of Blue-Emitting Phosphor Ba(K)-β-Al2O3:Eu2+ by Lattice Site Engineering for Full-Spectrum Lighting

“…Correspondingly, the researchers proposed a “full-spectrum strategy” to improve the quality of indoor light sources. Full-spectrum means that the emission wavelength of the lighting source continuously covers the range from 380 to 780 nm. − Generally, full-spectrum WLEDs can be achieved by combining near-ultraviolet (n-UV) or violet chips with multi-color phosphors. − Although the WLEDs based on n-UV chips have the advantage of good spectral continuity without a gap, human eyes have a low perception of n-UV light and excess n-UV light is harmful to the human body. , Therefore, violet chip-based full-spectrum WLEDs are more competitive.…”

“…15−19 Although the WLEDs based on n-UV chips have the advantage of good spectral continuity without a gap, human eyes have a low perception of n-UV light and excess n-UV light is harmful to the human body. 20,21 Therefore, violet chip-based full-spectrum WLEDs are more competitive.…”

Tunable ultra-broadband full-visible-spectral emission of Bi3+-doped aluminate phosphors enabled by structure transformation and site occupancy engineering

“…At the outset, the obtained LED suffers from high color temperature (T C 4 6000 K) and a low color rendering index (R a o 80) due to the lack of a red component. [5][6][7] Afterwards, this deficiency of such pc-WLEDs can be overcome by replacing the yellow emitting phosphor with another yellow emitting phosphor having a sufficient amount of red component or by mixing red-emitting phosphors together and then coating on a blue emitting chip. For example, by introducing an activator ion to achieve sufficient red light emission, Ma et al doped Pr 3+ and Mn 2+ into YAG:Ce 3+ to achieve a WLED chip with an R a of 84.8 and a CCT of 4272 K. 8 And Lian et al mixed Cs 2 GeF 6 :Mn 4+ with YAG:Ce 3+ to obtain a WLED with R a = 90.5 and CCT = 3385 K. 9 However, the sharp peak of the blue LED chip has negative effects on the human body.…”