scholarly journals A novel red-emitting phosphor Mg2Y2Al2Si2O12:Ce3+/Mn2+ for blue chip-based white LEDs

RSC Advances ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 2706-2717
Author(s):  
Zhipeng Wang ◽  
Zhijun Wang ◽  
Yuebin Li ◽  
Jinjin Liu ◽  
Qi Bao ◽  
...  
Keyword(s):  
Energy Transfer ◽  
Emission Spectra ◽  
White Leds ◽  
Blue Chip ◽  
Red Emitting Phosphor

The change of the emission spectra of Mg1.93Y2-xAl2Si2O12:0.07Ce3+, xMn2+ originates from the change of the structure and the energy transfer between ions.

scholarly journals Photoluminescence and energy transfer of YAG: Ce3+, Gd3+, Bi3+

2016 ◽  
Vol 06 (04) ◽  
pp. 1650029 ◽  
Author(s):  
Meidan Que ◽  
Wenxiu Que ◽  
Ting Zhou ◽  
Jinyou Shao ◽  
Lingbing Kong
Keyword(s):  
Crystal Structure ◽  
Energy Transfer ◽  
Emission Intensity ◽  
Emission Band ◽  
Emission Spectra ◽  
Excitation Band ◽  
Size Mismatch ◽  
White Leds ◽  
Orange Region ◽  
Potential Applications

In this study, Gd[Formula: see text] and Bi[Formula: see text] ions act to redshift the emission band to orange region, and to enhance significantly the maximum emission of YAG: Ce[Formula: see text]. On account that size mismatch between the host and the doped Gd[Formula: see text] ion, the crystal structure turns soft, and the emission spectra are not tuned from 540 to 570[Formula: see text]nm but decreased the emission intensity. Accordingly, an effective way to increase emission intensity is to introduce Bi[Formula: see text] ion into the YAG: Ce[Formula: see text], Gd[Formula: see text] phosphors. Experimental results show partial overlapping between the emission band of Bi[Formula: see text] ion and the excitation band of Ce[Formula: see text] ion, indicating that the energy transfer from Bi[Formula: see text] to Ce[Formula: see text] ions exists in the (Y[Formula: see text]Ce[Formula: see text]Gd)Al5O[Formula: see text]: Bi[Formula: see text] phosphor. Bi[Formula: see text] ion can serve as the activator to provide energy for Ce[Formula: see text] ion via cross relaxation phenomenon. Therefore, the (Y[Formula: see text]Ce[Formula: see text]Gd)Al5O[Formula: see text]: Bi[Formula: see text] phosphor could have potential applications in warm white LEDs.

scholarly journals A STUDY OF RED-EMITTING PHOSPHOR OF K2SiF6:Mn4+ FOR WARM WHITE LEDs

2018 ◽  
Vol 56 (1A) ◽  
pp. 183 ◽  
Author(s):  
Nguyen Le Anh
Keyword(s):  
Energy Transfer ◽  
Narrow Band ◽  
Light Emitting Diode ◽  
Forbidden States ◽  
Red Emission ◽  
Light Emitting ◽  
White Leds ◽  
Band Emission ◽  
Red Emitting Phosphor

This study focuses on the fabrication of red-emitting phosphor based on K2SiF6: Mn4+ phosphor. Characteristic emissive peaks in the red region of the Mn4+ ions involve the energy transfer from spin-forbidden states of 2Eg → 4A2, showing narrow band emission peaks at 609, 614, 631, 635 and 647 nm. Meanwhile, their absorptive peaks involve the energy transfer from spin-allowed states of 4A2 → 4Tg; the excited wavelength of the Mn4+ is in the range 360 - 460 nm. Thus, the K2SiF6: Mn4+ phosphor is particularly suitable for redundancy of 460 nm - Light Emitting Diode (LED); it complements the red emission of the commercial White LEDs.

Narrow-band red emitting phosphor BaTiF6:Mn4+: preparation, characterization and application for warm white LED devices

2016 ◽  
Vol 45 (44) ◽  
pp. 17886-17895 ◽  
Author(s):  
Xiaoli Gao ◽  
Yan Song ◽  
Guixia Liu ◽  
Xiangting Dong ◽  
Jinxian Wang ◽  
...  
Keyword(s):  
Narrow Band ◽  
White Led ◽  
White Leds ◽  
Blue Chip ◽  
Red Emitting Phosphor

A narrow-band red emitting BaTiF6:Mn4+phosphor with a microspindle morphology is applied to warm white LEDs by combination with a blue chip and YAG:Ce3+.

scholarly journals Melt-Spun Photoluminescent Polymer Optical Fibers for Color-Tunable Textile Illumination

Materials ◽  
2021 ◽  
Vol 14 (7) ◽  
pp. 1740
Author(s):  
Konrad Jakubowski ◽  
Manfred Heuberger ◽  
Rudolf Hufenus
Keyword(s):  
Energy Transfer ◽  
Optical Fibers ◽  
Color Space ◽  
Emission Spectra ◽  
Wide Range ◽  
Color Tunable ◽  
Melt Spun ◽  
Polymer Optical Fibers ◽  
Collective Emission ◽  
Down Conversion

The increasing interest in luminescent waveguides, applied as light concentrators, sensing elements, or decorative illuminating systems, is fostering efforts to further expand their functionality. Yarns and textiles based on a combination of distinct melt-spun polymer optical fibers (POFs), doped with individual luminescent dyes, can be beneficial for such applications since they enable easy tuning of the color of emitted light. Based on the energy transfer occurring between differently dyed filaments within a yarn or textile, the collective emission properties of such assemblies are adjustable over a wide range. The presented study demonstrates this effect using multicolor, meltspun, and photoluminescent POFs to measure their superimposed photoluminescent emission spectra. By varying the concentration of luminophores in yarn and fabric composition, the overall color of the resulting photoluminescent textiles can be tailored by the recapturing of light escaping from individual POFs. The ensuing color space is a mean to address the needs of specific applications, such as decorative elements and textile illumination by UV down-conversion.

scholarly journals Upconversion Luminescence of Silica–Calcia Nanoparticles Co-doped with Tm3+ and Yb3+ Ions

Materials ◽  
2021 ◽  
Vol 14 (4) ◽  
pp. 937
Author(s):  
Katarzyna Halubek-Gluchowska ◽  
Damian Szymański ◽  
Thi Ngoc Lam Tran ◽  
Maurizio Ferrari ◽  
Anna Lukowiak
Keyword(s):  
Energy Transfer ◽  
Near Infrared ◽  
Upconversion Luminescence ◽  
Sol Gel ◽  
Emission Spectra ◽  
Transmission Electron ◽  
Characteristic Emission ◽  
Diffraction Patterns ◽  
Size Of Particles ◽  
Average Size

Looking for upconverting biocompatible nanoparticles, we have prepared by the sol–gel method, silica–calcia glass nanopowders doped with different concentration of Tm3+ and Yb3+ ions (Tm3+ from 0.15 mol% up to 0.5 mol% and Yb3+ from 1 mol% up to 4 mol%) and characterized their structure, morphology, and optical properties. X-ray diffraction patterns indicated an amorphous phase of the silica-based glass with partial crystallization of samples with a higher content of lanthanides ions. Transmission electron microscopy images showed that the average size of particles decreased with increasing lanthanides content. The upconversion (UC) emission spectra and fluorescence lifetimes were registered under near infrared excitation (980 nm) at room temperature to study the energy transfer between Yb3+ and Tm3+ at various active ions concentrations. Characteristic emission bands of Tm3+ ions in the range of 350 nm to 850 nm were observed. To understand the mechanism of Yb3+–Tm3+ UC energy transfer in the SiO2–CaO powders, the kinetics of luminescence decays were studied.

Improving the CRI of Al2O3-YAG:Ce eutectic for high-power white LEDs applications: Energy-transfer and co-luminescence

2021 ◽  
Vol 121 ◽  
pp. 111415
Author(s):  
Hao Lu ◽  
Qingsong Song ◽  
Xiaodong Xu ◽  
Peng Liu ◽  
Jian Liu ◽  
...  
Keyword(s):  
Energy Transfer ◽  
High Power ◽  
White Leds

A novel tunable blue-green-emitting CaGdGaAl2O7:Ce3+,Tb3+ phosphor via energy transfer for UV-excited white LEDs

2015 ◽  
Vol 44 (17) ◽  
pp. 8100-8106 ◽  
Author(s):  
Chao Liang ◽  
Hongpeng You ◽  
Yibing Fu ◽  
Xiaoming Teng ◽  
Kai Liu ◽  
...  
Keyword(s):  
Energy Transfer ◽  
Green Emission ◽  
Relative Content ◽  
White Leds

By tuning the relative content of the doped ions, tunable blue-green emission can be obtained by irradiation at 365 nm.

Luminescence Linewidth Broadening and Nonradiative Energy Transfer Studies of Solid UO2+2-Datura

1992 ◽  
Vol 46 (9) ◽  
pp. 1376-1381 ◽  
Author(s):  
Huei-Yang D. Ke ◽  
Gary D. Rayson
Keyword(s):  
Energy Transfer ◽  
Emission Spectra ◽  
Blue Shift ◽  
Liquid Nitrogen Temperature ◽  
Peak Position ◽  
Nonradiative Energy Transfer ◽  
Wall Material ◽  
Transfer Model ◽  
Solution Ph ◽  
Linewidth Broadening

The emission spectra and fluorescence decay curves of solid UO2+2- Datura at liquid nitrogen temperature have been measured. The linewidth of the emission peaks of UO2+2 ions in UO2+2- Datura decreases with the UO2+2 concentration. This linewidth broadening phenomenon can be explained by the existence of resonance interactions between adjacent UO2+2- Datura species. The analysis of the emission peak position of the bound ions has been used to provide a measure of the electronic factors contributing to the interaction between the uranyl ion and phosphoryl and dicarboxyl moieties on the cell wall material. An observed blue shift of the uranyl fluorescence spectrum as a function of solution pH has been ascribed to a distortion of the normally linear O-U-O bond. An inter- and intra-molecular nonradiative energy transfer model has been successfully used to interpret the measured lifetime data of UO2+2- Datura.

Sign in / Sign up

Export Citation Format

Share Document