Versatile Syntheses of Various Homo- and Copolymers of Poly(1,4-Arylene Vinylene)S

1999 ◽  
Vol 598 ◽  
Author(s):  
R. E. Martin ◽  
B. S. Chuah ◽  
R. H. Riehn ◽  
F. Geneste ◽  
F. Cacialli ◽  
...  
Keyword(s):  
Optical Properties ◽  
Solid State ◽  
Considerable Increase ◽  
Blue Shift ◽  
Phenylene Vinylene ◽  
Substitution Pattern ◽  
Light Emitting ◽  
Light Emitting Devices ◽  
Turn On ◽  
Wavelength Absorption

ABSTRACTThe synthesis of poly(1,4-phenylene vinylene)s (PPVs) containing a 2,3-dialkoxy substitution pattern has been developed. Poly[2,3-bis(2-ethylhexyloxy)-1,4-phenylene vinylene)] (BEH-PPV, 4) was prepared and its optical properties compared with the recently discussed poly(2,3-dibutoxy-1,4-phenylene vinylene) (DB-PPV, 1), which showed in contrast to classical 2,5-substituted PPV derivatives a notable blue-shift of the longest-wavelength absorption (λmax) and a considerable increase of the solid-state photoluminescence (PL) efficiency. The two statistical PPV copolymers 5 and 6 comprising 2,3-dibutoxy and dimethyloctylsilyl- or 2,5-bis(dimethyloctylsilyl) side-chains, respectively, were synthesized via the Gilch dehydrohalogenation route. Double-layer light-emitting devices (LEDs) were demonstrated to combine high electroluminescence efficiencies with low turn-on voltages.

Photoluminescence Properties of Ca3Si2O7: Pr3+ Orange-Red Phosphors Prepared by High-Temperature Solid-State Method

2018 ◽  
Vol 73 (6) ◽  
pp. 555-558 ◽  
Author(s):  
Zhi-Qing Peng ◽  
Rong Chen ◽  
Wen-Lin Feng
Keyword(s):  
Crystal Structure ◽  
High Temperature ◽  
Solid State ◽  
Solid State Method ◽  
Light Emitting ◽  
Light Emitting Devices ◽  
Red Phosphors ◽  
Typical Sample ◽  
State Method ◽  
Xrd Patterns

AbstractNovel luminescent materials Ca3-xSi2O7: xPr3+ were successfully prepared by the high-temperature solid-state method. The crystal structure, morphology, and optical spectrum were characterised by X-ray diffraction (XRD), scanning electron microscopy (SEM), and spectroscopy, respectively. The XRD patterns of the samples indicate that the crystal structure is monoclinic symmetry. The SEM shows that the selected sample has good crystallinity although its appearance is irregular and scalelike. The peak of the excitation spectrum of the sample is located at around 449 nm, corresponding to 3H4→3P2 transition of Pr3+. The peak of the emission spectrum of the sample is situated at around 612 nm which is attributed to 3P0→3H6 transition of Pr3+, and the colour is orange-red. The optimum concentration for Pr3+ replaced Ca2+ sites in Ca3Si2O7: Pr3+ is 0.75 mol%. The lifetime (8.48 μs) of a typical sample (Ca2.9925Pr0.0075)Si2O7 is obtained. It reveals that orange-red phosphors Ca3-xSi2O7: xPr3+ possess remarkable optical properties and can be used in white light emitting devices.

Post-functionalized poly(N-vinylcarbazole)s as effective low turn-on-voltage phosphorescent-hosts in polymeric light emitting devices

2014 ◽  
Vol 52 ◽  
pp. 227-237 ◽  
Author(s):  
Yu-Xun Wang ◽  
Ching-Nan Chuang ◽  
Chiou-Ling Chang ◽  
Yi-Ting Wu ◽  
Chung-Yi Chang ◽  
...  
Keyword(s):  
Light Emitting ◽  
Light Emitting Devices ◽  
Turn On

Light-emitting devices based on a poly(p-phenylene vinylene) derivative with ion-coordinating side groups

1999 ◽  
Vol 86 (11) ◽  
pp. 6392-6395 ◽  
Author(s):  
J. Morgado ◽  
R. H. Friend ◽  
F. Cacialli ◽  
B. S. Chuah ◽  
S. C. Moratti ◽  
...  
Keyword(s):  
Phenylene Vinylene ◽  
Light Emitting ◽  
Light Emitting Devices

Substitution Effect on 2-(Oxazolinyl)-phenols: Emission Color-Tunable, Minimalistic Excited-State Intramolecular Proton Transfer (ESIPT)-based Luminophores

2021 ◽  
Author(s):  
Dominik Göbel ◽  
Pascal Rusch ◽  
Daniel Duvinage ◽  
Tim Stauch ◽  
Nadja C. Bigall ◽  
...  
Keyword(s):  
Optical Properties ◽  
Excited State ◽  
Solid State ◽  
Substitution Effect ◽  
Optical Characterization ◽  
Intramolecular Proton Transfer ◽  
Substitution Pattern ◽  
Emission Color ◽  
Color Tunable

The synthesis and optical characterization of novel single-benzene ESIPT-based fluorophores is described in solid state and in solution. Special attention is given towards the influence of their unique substitution pattern on their optical properties. Depending on this pattern, aggregation induced emission or aggregation caused quenching (ACQ) is observed in the solid state.<br>

One-pot synthesis of double silane-functionalized carbon dots with tunable emission and excellent coating properties for WLEDs application

2021 ◽  
Author(s):  
Wenbing Cao ◽  
Yuhan Wu ◽  
Xin Li ◽  
Xuanfeng Jiang ◽  
Yuhong Zhang ◽  
...  
Keyword(s):  
Optical Properties ◽  
Carbon Dots ◽  
Great Influence ◽  
Alkoxy Group ◽  
Color Temperature ◽  
Molar Ratio ◽  
Coating Properties ◽  
One Pot ◽  
Light Emitting ◽  
Light Emitting Devices

Abstract Silane-functionalized carbon dots (SiCDs) can be exploited as effective color converting materials for the solid-state light-emitting devices. However, most of SiCDs reported thus far have shown photoluminescence emissions in the blue and green spectral range, which limit them to construct an efficient white light-emitting diodes (WLEDs) due to the lack of long-wavelength emission. Herein, a series of double silane-functionalized carbon dots (DSiCDs) were prepared via a one-step solvothermal method. The results show that the organic functional group of the silane has great influence on the optical properties of DSiCDs and the number of alkoxy group in the silane has great influence on coating properties of DSiCDs. In addition, the DSiCDs prepared by (3-aminopropyl)triethoxysilane and N-[3-(Trimethoxysilyl)propyl]ethylenediamine with molar ratio of 7:3 show excellent optical properties with the maximum emission at 608 nm under 400 nm excitation. Furthermore, they can be completely dried within 1 h at room temperature to form fluorescent coating with high stability and strong adhesion to the substrate. Together with their excellent optical and coating properties, they can be directly coated on LED chips to prepare WLEDs, with a CIE coordinate of (0.33,0.31), color rendering index of 81.6, and color temperature of 5774 K.

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