Donor Acceptor Copolymers from Cyclopentannulation Polymerizations with Dicyclopenta[cd,jk]pyrene and Dicyclopenta[cd,lm]perylene Acceptors

10.26434/chemrxiv.12344258.v1 ◽

2020 ◽

Cited By ~ 1

Author(s):

Ain Uddin ◽

Kyle Plunkett

Keyword(s):

Thin Film ◽

Cyclic Voltammetry ◽

Light Absorption ◽

Visible Region ◽

Optoelectronic Properties ◽

Band Gaps ◽

Molecular Weights ◽

Palladium Catalyzed ◽

Donor Acceptor ◽

Film Absorption

A series of donor-acceptor copolymers with dicyclopenta[cd,jk]pyrene and dicyclopenta[cd,lm]perylene acceptor units was prepared via palladium catalyzed cyclopenta-annulation reactions. The acceptor units were paired with diethynyl containing donor groups based on benzo[1,2-b:4,5-b']dithiophene, thieno[3,2-b]thiophene, and 4-octyl-4H-dithieno[3,2-b:2',3'-d]pyrrole to create six polymer variants. The cyclopentannulation polymerization resulted in copolymers with molecular weights (Mn) of 6-14 kDa and broad light absorption in the visible region with band gaps of 1.38-1.85 eV. The synthetic methodology, as well as optoelectronic properties, including thin-film absorption and cyclic voltammetry, of the donor-acceptor copolymers are presented.<br> <br><br>

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Selenophene Bearing Low Band Gap Conjugated Polymers: Tuning Optoelectronic Properties via Fluorene and Carbazole as Donor Moieties

10.20944/preprints201805.0331.v1 ◽

2018 ◽

Author(s):

Mustafa Yasa ◽

Seza Goker ◽

Levent Toppare

Keyword(s):

Conjugated Polymers ◽

Visible Region ◽

Gel Permeation Chromatography ◽

13C Nmr Spectroscopy ◽

Optoelectronic Properties ◽

Polymerization Reaction ◽

Molecular Weights ◽

Reduction Potentials ◽

Oxidation Potentials ◽

Palladium Catalyzed

In this study, two donor-acceptor (D-A) type conjugated polymers namely PQSeCz and PQSeFl were designed and synthesized. Selenophene was incorporated as a π -bridge, quinoxaline as an acceptor unit while carbazole and fluorene were used as the donor units. Polymers were synthesized via palladium catalyzed Suzuki polymerization reaction. All molecules were characterized by 1H and 13C NMR Spectroscopy. The weight and number average molecular weights of the two polymers were determined by gel permeation chromatography (GPC). Electrochemical and spectroelectrochemical characterizations of the polymers were performed to investigate their optoelectronic properties. Oxidation potentials were 1.15 V/ 0.82 V and 1.11 V/ 0.82 V for PQSeCz and PQSeFl respectively, while reduction potentials were -1.26 V /-1.14 V and -1.48 V/ -1.23 V, respectively. In the visible region, maximum absorption wavelengths for the two polymers were 551 nm and 560 nm, respectively. Optical band gaps (Egop) were found from the lowest energy π – π&lowast; transition onsets as 1.71 eV and 1.58 eV, respectively. Both polymers showed good solubility in common solvents.

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Synthesis, Crystallography, Microstructure, Crystal Defects, Optical and Optoelectronic Properties of ZnO:CeO2 Mixed Oxide Thin Films

Photonics ◽

10.3390/photonics7040112 ◽

2020 ◽

Vol 7 (4) ◽

pp. 112

Author(s):

Qais M. Al-Bataineh ◽

Mahmoud Telfah ◽

Ahmad A. Ahmad ◽

Ahmad M. Alsaad ◽

Issam A. Qattan ◽

...

Keyword(s):

Thin Film ◽

Thin Films ◽

Refractive Index ◽

Mixed Oxide ◽

Visible Region ◽

Functional Materials ◽

Crystal Defects ◽

Optoelectronic Properties ◽

Oxide Thin Films ◽

Pure Ceo2

We report the synthesis and characterization of pure ZnO, pure CeO2, and ZnO:CeO2 mixed oxide thin films dip-coated on glass substrates using a sol-gel technique. The structural properties of as-prepared thin film are investigated using the XRD technique. In particular, pure ZnO thin film is found to exhibit a hexagonal structure, while pure CeO2 thin film is found to exhibit a fluorite cubic structure. The diffraction patterns also show the formation of mixed oxide materials containing well-dispersed phases of semi-crystalline nature from both constituent oxides. Furthermore, optical properties of thin films are investigated by performing UV–Vis spectrophotometer measurements. In the visible region, transmittance of all investigated thin films attains values as high as 85%. Moreover, refractive index of pure ZnO film was found to exhibit values ranging between 1.57 and 1.85 while for CeO2 thin film, it exhibits values ranging between 1.73 and 2.25 as the wavelength of incident light decreases from 700 nm to 400 nm. Remarkably, refractive index of ZnO:CeO2 mixed oxide-thin films are tuned by controlling the concentration of CeO2 properly. Mixed oxide-thin films of controllable refractive indices constitute an important class of smart functional materials. We have also investigated the optoelectronic and dispersion properties of ZnO:CeO2 mixed oxide-thin films by employing well-established classical models. The melodramatic boost of optical and optoelectronic properties of ZnO:CeO2 mixed oxide thin films establish a strong ground to modify these properties in a skillful manner enabling their use as key potential candidates for the fabrication of scaled optoelectronic devices and thin film transistors.

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Synthesis and optoelectronic properties of benzoquinone-based donor–acceptor compounds

Beilstein Journal of Organic Chemistry ◽

10.3762/bjoc.15.285 ◽

2019 ◽

Vol 15 ◽

pp. 2914-2921

Author(s):

Daniel R Sutherland ◽

Nidhi Sharma ◽

Georgina M Rosair ◽

Ifor D W Samuel ◽

Ai-Lan Lee ◽

...

Keyword(s):

Charge Transfer ◽

Delayed Fluorescence ◽

Optoelectronic Properties ◽

Donor Group ◽

Thermally Activated Delayed Fluorescence ◽

Thermally Activated ◽

Palladium Catalyzed ◽

Donor Acceptor

Herein, we report a mild and efficient palladium-catalyzed C–H functionalization method to synthesize a series of benzoquinone (BQ)-based charge-transfer (CT) derivatives in good yields. The optoelectronic properties of these compounds were explored both theoretically and experimentally and correlations to their structures were identified as a function of the nature and position of the donor group (meta and para) attached to the benzoquinone acceptor. Compound 3, where benzoquinone is para-conjugated to the diphenylamine donor group, exhibited thermally activated delayed fluorescence (TADF) with a biexponential lifetime characterized by a prompt ns component and a delayed component of 353 μs.

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Novel low-band-gap conjugated polymers using an alternating donor/acceptor repeat unit

e-Polymers ◽

10.1515/epoly.2010.10.1.774 ◽

2010 ◽

Vol 10 (1) ◽

Author(s):

Phimwipha Piyakulawat ◽

Anusit Keawprajak ◽

Anon Chindaduang ◽

Anke Helfer ◽

Udom Asawapirom

Keyword(s):

Cyclic Voltammetry ◽

Charge Transfer ◽

Conjugated Polymers ◽

Lower Energy ◽

Intramolecular Charge Transfer ◽

Repeat Unit ◽

Band Gaps ◽

Donor And Acceptor ◽

Donor Acceptor ◽

Positive Step

AbstractA series of new π-conjugated donor-acceptor copolymers, based on a naphthalene-bisimide moiety as the electron-acceptor and connected to either thiophene or dialkylfluorene as the electron-donor, were synthesized. The polymers are soluble in common organic solvents. The UV-Vis spectra of the copolymers in chloroform showed two absorption maxima at higher energies (ca. 301 - 364 nm), assigned to the π-π * transition, and at a lower energy (ca. 512 - 595 nm), ascribed to the intramolecular charge transfer between donor and acceptor units. Cyclic voltammetry revealed that the polymers were susceptible to both electrochemical oxidation and reduction, and they had a LUMO and HOMO levels ranging from -4.07 to -3.80 eV and -6.13 to -5.64 eV, respectively. The energy band gaps were estimated to be 1.48 - 2.06 eV. These results represent a positive step towards making novel compounds suitable for electronic applications.

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Thiophene-based donor–acceptor co-oligomers by copper-catalyzed 1,3-dipolar cycloaddition

Beilstein Journal of Organic Chemistry ◽

10.3762/bjoc.8.76 ◽

2012 ◽

Vol 8 ◽

pp. 683-692 ◽

Cited By ~ 23

Author(s):

Stefanie Potratz ◽

Amaresh Mishra ◽

Peter Bäuerle

Keyword(s):

Cyclic Voltammetry ◽

Conjugated Polymers ◽

Sodium Azide ◽

Copper Catalyst ◽

Optoelectronic Properties ◽

Dipolar Cycloaddition ◽

One Pot ◽

Vis Spectroscopy ◽

Donor Type ◽

Donor Acceptor

Herein we present a three-component one-pot procedure to synthesize co-oligomers of a donor–acceptor–donor type, in which thiophene moieties work as donor and 1,2,3-triazoles as acceptor units. In this respect, terminally ethynylated (oligo)thiophenes were coupled to halogenated (oligo)thiophenes in the presence of sodium azide and a copper catalyst. Optoelectronic properties of various thiophene-1,2,3-triazole co-oligomers were investigated by UV–vis spectroscopy and cyclic voltammetry. Several co-oligomers were electropolymerized to the corresponding conjugated polymers.

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Palladium catalyzed cross-coupling reactions of difunctional derivatives Bu3SnArBr. Synthesis of regioregular poly(3-alkylthiophenes) and poly(4-alkyl 2,2'-bithiophenes) with high molecular weights

Journal de Chimie Physique ◽

10.1051/jcp:1998259 ◽

1998 ◽

Vol 95 (6) ◽

pp. 1250-1253 ◽

Cited By ~ 5

Author(s):

J.-P. Lère-Porte ◽

J. J.E. Moreau ◽

C. Torreilles

Keyword(s):

Cross Coupling ◽

Coupling Reactions ◽

Molecular Weights ◽

Cross Coupling Reactions ◽

Regioregular Poly ◽

Palladium Catalyzed

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Plasmon-Enhanced Sunlight Harvesting in Thin-Film Solar Cell by Randomly Distributed Nanoparticle Array

Materials ◽

10.3390/ma14061380 ◽

2021 ◽

Vol 14 (6) ◽

pp. 1380

Author(s):

Marwa M. Tharwat ◽

Ashwag Almalki ◽

Amr M. Mahros

Keyword(s):

Thin Film ◽

Solar Cells ◽

Solar Cell ◽

Near Infrared ◽

Structural Parameters ◽

Visible Region ◽

Nanoparticle Array ◽

Solar Energy Harvesting ◽

Infra Red ◽

Crucial Parameter

In this paper, a randomly distributed plasmonic aluminum nanoparticle array is introduced on the top surface of conventional GaAs thin-film solar cells to improve sunlight harvesting. The performance of such photovoltaic structures is determined through monitoring the modification of its absorbance due to changing its structural parameters. A single Al nanoparticle array is integrated over the antireflective layer to boost the absorption spectra in both visible and near-infra-red regimes. Furthermore, the planar density of the plasmonic layer is presented as a crucial parameter in studying and investigating the performance of the solar cells. Then, we have introduced a double Al nanoparticle array as an imperfection from the regular uniform single array as it has different size particles and various spatial distributions. The comparison of performances was established using the enhancement percentage in the absorption. The findings illustrate that the structural parameters of the reported solar cell, especially the planar density of the plasmonic layer, have significant impacts on tuning solar energy harvesting. Additionally, increasing the plasmonic planar density enhances the absorption in the visible region. On the other hand, the absorption in the near-infrared regime becomes worse, and vice versa.

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Synthesis of π-Conjugated Polymers Containing Benzotriazole Units via Palladium-Catalyzed Direct C-H Cross-Coupling Polycondensation for OLEDs Applications

Polymers ◽

10.3390/polym13020254 ◽

2021 ◽

Vol 13 (2) ◽

pp. 254

Author(s):

Dong Han ◽

Jingwen Li ◽

Qiang Zhang ◽

Zewang He ◽

Zhiwei Wu ◽

...

Keyword(s):

Conjugated Polymers ◽

Quantum Efficiency ◽

Cross Coupling ◽

Building Blocks ◽

Gravimetric Analysis ◽

19F Nmr Spectra ◽

Light Emitting ◽

Molecular Weights ◽

Palladium Catalyzed ◽

Red Luminescence

Four D-π-A conjugated polymers, namely P1–P4, which contain benzotriazole building blocks in their backbone as acceptor, are synthesized via palladium-catalyzed direct C-H cross-coupling polycondensation of 5,6-difluorobenzotriazole with different thiophene derivatives, including 3-octylthiophene, 2,2’-bithiophene, thieno[3,4-b][1,4]dioxine, and 4,4-dioctyl-4H-silolo-[3,2-b:4,5-b’]dithiophene as donor units, respectively. Taking the polymer P1 as an example, the chemical structure of the polymer is demonstrated by 1H and 19F NMR spectra. The optical, electrochemical, and thermal properties of these polymers are assessed by UV–vis absorption and fluorescence spectroscopy, cyclic voltammetry (CV), and thermal gravimetric analysis (TGA), respectively. DFT simulations of all polymers are also performed to understand their physicochemical properties. Furthermore, P1 and P2, which have relatively higher molecular weights and better fluorescent quantum efficiency than those of P3 and P4, are utilized as lighting emitters for organic light-emitting diodes (OLEDs), affording promising green and red luminescence with 0.07% and 0.14% of maximum external quantum efficiency, respectively, based on a device with an architecture of ITO/PEDOT:PSS/PTAA/the polymer emitting layer/TPBi/LiF/Al.

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