Stable white photoluminescence from Mn-contained organic lead bromide perovskite ring arrays formed from 2D colloidal crystal templates

2020 ◽  
Vol 44 (32) ◽  
pp. 13619-13625
Author(s):  
Jingkun Xu ◽  
Junfeng Qu ◽  
Haibao Shao ◽  
Shuhong Xu ◽  
Chunlei Wang ◽  
...  

C4N2H14PbxMn1−xBr4 perovskite ring arrays with stable white light emission and controllable size for high color quality white light-emitting diodes.

2021 ◽  
Vol 10 (4) ◽  
pp. 1930-1935
Author(s):  
Phan Xuan Le ◽  
Le Hung Tien

Among the structures using for fabricating white light-emitting diodes (WLEDs) such as the conformal coating or in-cup geometries, the remote phosphor structure gives the highest luminous efficacy. However, in terms of color quality, its performance is not as good as the others. The red-light compensation has been reported as the effective solution for enhancing the color quality of WLEDs. Hence, this study adopted the idea and applied to the dual-layer phosphor structure. The phosphor used to boost the red color in light formation is (Y,Gd)BO3:Eu particle. The dual-layer remote phosphor structure was simulated with the red (Y,Gd)BO3:Eu phosphor layer above the original yellow phosphor YAG:Ce3+ one. The WLEDs with different correlated color temperatures of 5600 K, 6600 K and 7700K were experimented. Mie-theory and Lambert-Beer law were applied to examine the results. The growth in color rendering index (CRI) and color quality scale (CQS) with the increase of (Y,Gd)BO3:Eu phosphor concentration was observed. Nevertheless, the lumen efficacy would be degraded if the concentration was over a certain number. The information provided in this article is useful for the development of high-power WLED production with greater color quality.


Joule ◽  
2018 ◽  
Vol 2 (5) ◽  
pp. 914-926 ◽  
Author(s):  
Zhenbin Wang ◽  
Jungmin Ha ◽  
Yoon Hwa Kim ◽  
Won Bin Im ◽  
Joanna McKittrick ◽  
...  

2015 ◽  
Vol 3 (3) ◽  
pp. 607-615 ◽  
Author(s):  
Ji Hye Oh ◽  
Heejoon Kang ◽  
Yun Jae Eo ◽  
Hoo Keun Park ◽  
Young Rag Do

In this study, we synthesized and characterized narrow-band red-emitting K2SiF6:Mn4+ phosphors in order to improve the color qualities of warm white light-emitting diodes (LEDs).


2016 ◽  
Vol 22 (1) ◽  
pp. 35-41 ◽  
Author(s):  
Huang-Yu Lin ◽  
Sheng-Wen Wang ◽  
Chien-Chung Lin ◽  
Kuo-Ju Chen ◽  
Hau-Vei Han ◽  
...  

2013 ◽  
Vol 1538 ◽  
pp. 371-375
Author(s):  
Zhao Si ◽  
Tongbo Wei ◽  
Jun Ma ◽  
Ning Zhang ◽  
Zhe Liu ◽  
...  

ABSTRACTA study about the achievement of dichromatic white light-emitting diodes (LEDs) was performed. A series of dual wavelength LEDs with different last quantum-well (LQW) structure were fabricated. The bottom seven blue light QWs (close to n-GaN layer) of the four samples were the same. The LQW of sample A was 3 nm, and that of sample B, C and D were 6 nm, a special high In content ultra-thin layer was inserted in the middle of the LQW of sample C and on top of that of sample D. XRD results showed In concentration fluctuation and good interface quality of the four samples. PL measurements showed dual wavelength emitting, the blue light peak position of the four samples were almost the same, sample A with a narrower LQW showed an emission wavelength much shorter than that of sample B, C, D. EL measurement was done at an injection current of 100 mA. Sample A only showed LQW emission due to holes distribution. Because of wider LQW, the emission wavelength of sample B, C and D was longer and peak intensity was weaker. Sample D with insert layer on top of LQW showed strongest yellow light emission with a blue peak. As the injection current increased, sample A showed highest output light power due to narrower LQW. Of the other three samples with wider LQW, sample D showed highest output power. Effective yellow light emission has always been an obstacle to the achievement of dichromatic white LED. Sample D with insert layer close to p-GaN can confine the hole distribution more effectively hence the recombination of holes and electrons was enhanced, the yellow light emission was improved and dichromatic white LED was achieved.


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