A Triple-Doped Phosphor Strategy for the Conversion of Cool and Warm White Light

Abstract

This work proposes a new type of Eu2+, Ce3+, Mn2+ codoped strategy that can be adapted to both ultraviolet (UV) and blue chips to achieve high-quality white light illumination. Primarily, the target sample was confirmed by X-ray diffraction (XRD) and Rietveld refinement, and the surface morphology and element distribution were observed by scanning electron microscopy (SEM). Second, the energy transfer behavior and mechanism were determined by studying double-doped samples. Lu2Mg2Al2Si2O12: Eu2+,Ce3+ (LMAS: Eu2+,Ce3+) can realize an emission color adjustment from blue to yellow. The emission color of LMAS: Ce3+,Mn2+ can be adjusted from light yellow to orange yellow. Afterward, the triple-doped sample exhibits full-spectrum emission under the excitation at 365 nm, and yellow emission under the excitation at 450 nm. When combined with a 365 nm chip, the obtained light-emitting diode (LED) devices can achieve warm white light with a color rendering index (Ra) of 96.6, light emission (LE) of 1.79 lm/W, and correlated color temperature (CCT) of 4874 K. When this phosphor was combined with a 460 nm chip, cold white light with Ra = 70, LE = 13.57 lm/W, and CCT = 5782 K can be achieved. Finally, according to the properties of the phosphor, a conceptual diagram of a new type parallel device was designed, which can easily and effectively realize the conversion of cold and warm white light. This work provides a new idea for the design of single-substrate white light phosphor and proposes a new parallel device concept, which is expected to be applied in the field of lighting.

Crystal Structure, Photoluminescence, and “Abnormal” High Stability of Ca3Y(GaO)3(BO3)4: Dy3+/Sm3+/La3+ for n-UV wLEDs

“…The phosphor obtained via the solid-phase reaction exhibits irregularly shaped particles with sizes several microns in diameter (Figure a). This morphology is helpful for application in the SSL as it can realize high packing density and low light scattering losses. − EDS is also performed to examine the presence of elements and their distributions (Figure b), where it confirms that the phosphor is exclusively made up of the elements Ca, Y, Ga, B, Dy, Sm, La, and O. Importantly, these elements are distributed uniformly across the entire particle without aggregation and phase separation.…”

Highly‐Sensitive, Tri‐Modal Luminescent Manometer Utilizing Band‐Shift, Ratiometric and Lifetime‐Based Sensing Parameters

“…Moreover, the broadband nature of the emission introduces a potential source of imprecision when Figure 8. Pressure-dependent maximum of the emission band associated with the 4 T 2g → 4 A 2g transition of Cr 3+ ions in doped Li 3 Sc 2 (PO 4 ) 3 (1% Cr 3+ ), with the pressure range defined as the operating range, where a linear dependence of the band centroid as a function of pressure was obtained a); A summary of the most sensitive luminescence manometers in terms of pressure-induced spectral shift rate of the emission band (>1 nm GPa −1 ) b) [6,8,14,37,[43][44][45][46][47][48][49][50][51][52][53][54][55][56] and a d𝜆/dp versus d𝜆/dT plot for representative luminescence manometers based on the spectral shift-c).…”

Investigation of the luminescence properties and energy transfer mechanisms in Gd3TaO7:Bi3+,Eu3+ phosphors for their potential application in full-spectrum WLEDs

“…Several single-phase white light-emitting phosphors based on energy transfer between multi-doped ions have been reported, including Eu 2+ -Mn 2+ , Tb 3+ -Eu 3+ , Dy 3+ -Eu 3+ , Bi 3+ -Eu 3+ and Ce 3+ -Mn 2+ . [22][23][24][25][26][27][28] Among these options, the doping system of Bi 3+ -Eu 3+ ion pairs appears to be a highly promising candidate.…”