Red‐Light‐Emitting System Based on Aggregation of Donor–Acceptor Derivatives in Polar Aqueous Media

2012 ◽  
Vol 7 (7) ◽  
pp. 1553-1557 ◽  
Author(s):  
Tsutomu Ishi‐i ◽  
Kei Ikeda ◽  
Yuki Kichise ◽  
Michiaki Ogawa
Keyword(s):  
Aqueous Media ◽  
Red Light ◽  
Light Emitting ◽  
Donor Acceptor

scholarly journals Study on the Color-Compensation Effect of Composite Orange-Red Quantum Dots in WLED Application

2020 ◽  
Author(s):  
Xiaoyue Hu ◽  
Yangyang Xie ◽  
Chong Geng ◽  
Shu Xu ◽  
Wengang Bi
Keyword(s):  
Quantum Dots ◽  
Light Emitting Diode ◽  
Red Light ◽  
Resonance Energy Transfer ◽  
Resonance Energy ◽  
Light Emitting ◽  
Light Region ◽  
Color Compensation ◽  
Donor Acceptor ◽  
Color Rendering

Abstract Quantum dots (QDs) as emerging light-converting materials show the advantage of enhancing color quality of white light-emitting diode (WLED). However, WLEDs employing narrow-emitting monochromic QDs usually present unsatisfactory color rendering in the orange region. Herein, composite orange-red QDs (composite-QDs) are developed through mixing CdSe/ZnS based orange QDs (O-QDs) and red QDs (R-QDs) to compensate the orange-red light for WLEDs. We investigated the effect of self-absorption and fluorescence resonance energy transfer (FRET) process in composite-QDs on the spectral controllability and fluorescent quenching in WLEDs. The concentration and donor/acceptor ratios were also taken into account to analyze the FRET efficiency and help identify suitable composite-QDs for color compensation in the orange-red light region. As the result, the optimized composite-QDs effectively improve the color rendering index of the WLED compared with monochromatic QDs.

Study on the Color-Compensation Effect of Hybrid Orange-Red Quantum Dots in WLED Application

2020 ◽  
Author(s):  
Xiaoyue Hu ◽  
Yangyang Xie ◽  
Chong Geng ◽  
Shu Xu ◽  
Wengang Bi
Keyword(s):  
Quantum Dots ◽  
Light Emitting Diode ◽  
Red Light ◽  
Resonance Energy Transfer ◽  
Resonance Energy ◽  
Light Emitting ◽  
Light Region ◽  
Color Compensation ◽  
Donor Acceptor ◽  
Color Rendering

Abstract Quantum dots (QDs) as emerging light-converting materials show the advantage of enhancing color quality of white light-emitting diode (WLED). However, WLEDs employing narrow-emitting monochromic QDs usually present unsatisfactory color rendering in the orange region. Herein, orange-red emitting polychromic hybrid QDs (hybrid-QDs) are developed through mixing CdSe/ZnS based orange QDs (O-QDs) and red QDs (R-QDs) to compensate the orange-red light for WLEDs. We investigated the effect of self-absorption and fluorescence resonance energy transfer (FRET) process in hybrid-QDs on the spectral controllability and fluorescent quenching in WLEDs. The concentration and donor/acceptor ratios were also taken into account to analyze the FRET efficiency and help identify suitable hybrid-QDs for color compensation in the orange-red light region. As the result, the optimized hybrid-QDs effectively improve the color rendering index of the WLED compared with monochromatic QDs at the same color coordinates.

scholarly journals Understanding the luminescent nature of organic radicals for efficient doublet emitters and pure-red light-emitting diodes

2020 ◽  
Vol 19 (11) ◽  
pp. 1224-1229 ◽  
Author(s):  
Alim Abdurahman ◽  
Timothy J. H. Hele ◽  
Qinying Gu ◽  
Jiangbin Zhang ◽  
Qiming Peng ◽  
...  
Keyword(s):  
Light Emitting Diodes ◽  
Red Light ◽  
Organic Radicals ◽  
Light Emitting

scholarly journals Photocatalytic Degradation of Sulfolane Using a LED-Based Photocatalytic Treatment System

Catalysts ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 624
Author(s):  
Sripriya Dharwadkar ◽  
Linlong Yu ◽  
Gopal Achari
Keyword(s):  
Photocatalytic Degradation ◽  
Oil And Gas ◽  
Light Emitting Diode ◽  
Tap Water ◽  
Aqueous Media ◽  
Ultrapure Water ◽  
Light Emitting ◽  
Degradation Rates ◽  
Reduced Graphene ◽  
The Impact

Sulfolane is an emerging industrial pollutant detected in the environments near many oil and gas plants in North America. So far, numerous advanced oxidation processes have been investigated to treat sulfolane in aqueous media. However, there is only a few papers that discuss the degradation of sulfolane using photocatalysis. In this study, photocatalytic degradation of sulfolane using titanium dioxide (TiO2) and reduced graphene oxide TiO2 composite (RGO-TiO2) in a light-emitting diode (LED) photoreactor was investigated. The impact of different waters (ultrapure water, tap water, and groundwater) and type of irradiation (UVA-LED and mercury lamp) on photocatalytic degradation of sulfolane were also studied. In addition, a reusability test was conducted for the photocatalyst to examine the degradation of sulfolane in three consecutive cycles with new batches of sulfolane-contaminated water. The results show that LED-based photocatalysis was effective in degrading sulfolane in waters even after three photocatalytic cycles. UVA-LEDs displayed more efficient use of photon energy when compared with the mercury lamps as they have a narrow emission spectrum coinciding with the absorption of TiO2. The combination of UVA-LED and TiO2 yielded better performance than UVA-LED and RGO-TiO2 for the degradation of sulfolane. Much lower sulfolane degradation rates were observed in tap water and groundwater than ultrapure water.

scholarly journals Oligofuran–Benzothiadiazole Co-oligomers: Synthesis, Optoelectronic Properties and Reactivity

2021 ◽  
Vol 03 (02) ◽  
pp. 303-308
Author(s):  
Dror Ben Abba Amiel ◽  
Choongik Kim ◽  
Ori Gidron
Keyword(s):  
Organic Solar Cells ◽  
Field Effect ◽  
Field Effect Transistors ◽  
Organic Light Emitting Diodes ◽  
Organic Field Effect Transistors ◽  
Active Materials ◽  
Light Emitting ◽  
Organic Light ◽  
Donor Acceptor ◽  
Optical Bandgaps

Donor–acceptor–donor (DAD) triad systems are commonly applied as active materials in ambipolar organic field-effect transistors, organic solar cells, and NIR-emitting organic light-emitting diodes. Often, these triads utilize oligothiophenes as donors, whereas their oxygen-containing analogs, oligofurans, are far less studied in this setup. Here we introduce a family of DAD triads in which the donors are oligofurans and the acceptor is benzothiadiazole. In a combined computational and experimental study, we show that these triads display optical bandgaps similar to those of their thiophene analogs, and that a bifuran donor is sufficient to produce emission in the NIR spectral region. The presence of a central acceptor unit increases the photostability of oligofuran-based DAD systems compared with parent oligofurans of the similar length.

scholarly journals Red Light-Emitting Diodes with All-Inorganic CsPbI3/TOPO Composite Nanowires Color Conversion Films

2020 ◽  
Vol 15 (1) ◽  
Author(s):  
Lung-Chien Chen ◽  
Yi-Tsung Chang ◽  
Ching-Ho Tien ◽  
Yu-Chun Yeh ◽  
Zong-Liang Tseng ◽  
...  
Keyword(s):  
Quantum Dots ◽  
Light Emitting Diode ◽  
Red Light ◽  
Trioctylphosphine Oxide ◽  
Optical And Electrical Properties ◽  
Colloidal Solutions ◽  
High Quality ◽  
Light Emitting ◽  
Hot Injection ◽  
Color Conversion

AbstractThis work presents a method for obtaining a color-converted red light source through a combination of a blue GaN light-emitting diode and a red fluorescent color conversion film of a perovskite CsPbI3/TOPO composite. High-quality CsPbI3 quantum dots (QDs) were prepared using the hot-injection method. The colloidal QD solutions were mixed with different ratios of trioctylphosphine oxide (TOPO) to form nanowires. The color conversion films prepared by the mixed ultraviolet resin and colloidal solutions were coated on blue LEDs. The optical and electrical properties of the devices were measured and analyzed at an injection current of 50 mA; it was observed that the strongest red light intensity was 93.1 cd/m2 and the external quantum efficiency was 5.7% at a wavelength of approximately 708 nm when CsPbI3/TOPO was 1:0.35.

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