- The effect of aromatic ring size in electron deficient semiconducting polymers for n-type organic thermoelectrics
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N-type semiconducting polymers have been recently utilized in thermoelectric devices, however they have typically exhibited low electrical conductivities and poor device stability, in contrast to p-type semiconductors, which have been much higher performing. This is due in particular to the n-type semiconductor's low doping efficiency, and poor charge carrier mobility. Strategies to enhance the thermoelectric performance of n-type materials include optimizing the electron affinity (EA) with respect to the dopant to improve the doping process and increasing the charge carrier mobility through enhanced molecular packing. Here, we report the design, synthesis and characterization of fused electron-deficient n-type copolymers incorporating the electron withdrawing lactone unit along the backbone. The polymers were synthesized using metal-free aldol condensation conditions to explore the effect of enlarging the central phenyl ring to a naphthalene ring, on the electrical conductivity. When n-doped with N-DMBI, electrical conductivities of up to 0.28 S cm-1, Seebeck coefficients of -75 μV K-1 and maximum Power factors of 0.16 μW m-1 K-2 were observed from the polymer with the largest electron affinity of -4.68 eV. Extending the aromatic ring reduced the electron affinity, due to reducing the density of electron withdrawing groups and subsequently the electrical conductivity reduced by almost two orders of magnitude. This journal is
- Alsufyani, Maryam,Bristow, Helen,Chen, Hu,Chen, Xingxing,Fabiano, Simone,Hallani, Rawad K.,Ji, Xudong,McCulloch, Iain,Paulsen, Bryan D.,Rivnay, Jonathan,Sirringhaus, Henning,Wang, Suhao,Xiao, Mingfei,Xu, Kai
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p. 15150 - 15157
(2020/11/23)
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- NB 06: From a simple lysosomotropic aSMase inhibitor to tools for elucidating the role of lysosomes in signaling apoptosis and LPS-induced inflammation
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Ceramide generation is involved in signal transduction of cellular stress response, in particular during stress-induced apoptosis in response to stimuli such as minimally modified Low-density lipoproteins, TNFalpha and exogenous C6-ceramide. In this paper we describe 48 diverse synthetic products and evaluate their lysosomotropic and acid sphingomyelinase inhibiting activities in macrophages. A stimuli-induced increase of C16-ceramide in macrophages can be almost completely suppressed by representative compound NB 06 providing an effective protection of macrophages against apoptosis. Compounds like NB 06 thus offer highly interesting fields of application besides prevention of apoptosis of macrophages in atherosclerotic plaques in vessel walls. Most importantly, they can be used for blocking pH-dependent lysosomal processes and enzymes in general as well as for analyzing lysosomal dependent cellular signaling. Modulation of gene expression of several prominent inflammatory messengers IL1B, IL6, IL23A, CCL4 and CCL20 further indicate potentially beneficial effects in the field of (systemic) infections involving bacterial endotoxins like LPS or infections with influenza A virus.
- Blaess, Markus,Bibak, Nelly,Claus, Ralf A.,Kohl, Matthias,Bonaterra, Gabriel A.,Kinscherf, Ralf,Laufer, Stefan,Deigner, Hans-Peter
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supporting information
p. 73 - 104
(2017/10/17)
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- Multifunctional geometrical isomers of ferrocene-benzo[1,2-b:4,5-b′]difuran-2,6-(3H,7H)-dione adducts: second-order nonlinear optical behaviour and charge transport in thin film OFET devices
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Geometrical isomers of a set of new ferrocene-benzo[1,2-b:4,5-b′]difuran-2,6-(3H,7H)-dione dyads were synthesized and their optical, nonlinear optical (NLO) and electrochemical properties were investigated. The compounds were fully characterized by spectroscopic data and single crystal X-ray analysis in few cases. The second-order nonlinear polarizabilities were measured in chloroform using a femtosecond hyper-Rayleigh scattering (HRS) method at 1300 nm. The dyads exhibit structure-dependent NLO properties, which could be rationalized by correlation with electrochemical and theoretical data. The (Z)-6 chromophore recorded higher βHRS values than the corresponding (E)-6 isomer, in the donor-acceptor (D-A) type dyads. Similarly, in D-A-D chromophore 7, the βHRS values of isomers follow the order (Z,Z) > (E,Z) > (E,E), which matches with the trend of the wavelength of their maximum absorption as well as an increasing band gap in that order. Owing to the inbuilt structural features, two of these D-A compounds were also explored as semiconducting materials in vacuum deposited top contact bottom gated thin film organic field-effect transistors (OFETs). Defying steric restrictions of the ferrocene unit, the triad (Z,Z)-7 depicted an unbalanced (μe: 3 × 10?3 cm?2 V?1 s?1 and μh: 7 × 10?5 cm?2 V?1 s?1) charge transport behaviour. Evaluation of the isomers of the type studied in this investigation constitutes one of very few reports, in particular this study reveals for the first time the semiconducting behaviour of thermally stable redox active Fc based semiconductors.
- Singla, Priya,Van Steerteghem, Nick,Kaur, Navdeep,Ashar,Kaur, Paramjit,Clays, Koen,Narayan,Singh, Kamaljit
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p. 697 - 708
(2017/01/28)
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- Electron-Deficient Poly(p-phenylene vinylene) Provides Electron Mobility over 1 cm2 V-1 s-1 under Ambient Conditions
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Poly(p-phenylene vinylene) derivatives (PPVs) are one of the most widely investigated p-type polymers in organic electronics. PPVs generally exhibit electron mobilities lower than 10-4 cm2 V-1 s-1, thus hindering their applications in high-performance polymer field-effect transistors and organic photovoltaics. Herein, we design and synthesize a novel electron-deficient PPV derivative, benzodifurandione-based PPV (BDPPV). This new PPV derivative displays high electron mobilities up to 1.1 cm2 V-1 s-1 under ambient conditions (4 orders of magnitude higher than those of other PPVs), because it overcomes common defects in PPVs, such as conformational disorder, weak interchain interaction, and a high LUMO level. BDPPV represents the first polymer that can transport electrons over 1 cm2 V-1 s-1 under ambient conditions.
- Lei, Ting,Dou, Jin-Hu,Cao, Xiao-Yu,Wang, Jie-Yu,Pei, Jian
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p. 12168 - 12171
(2013/09/23)
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- Design of protonated polyazamacrocycles based on phenanthroline motifs for selective uptake of aromatic carboxylate anions and herbicides
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Three novel large polyazamacrocycles containing two 1,10-phenanthroline (phen) units connected by two polyamine spacers of different length, [32]phen2N4, [30]phen2N6 and Me 2[34]phen2N6, have been synthesised and their protonated forms used as receptors for binding studies with several aromatic carboxylate anions (benzoate (bzc-), 1-naphthalate (naphc -), 9-anthracenate (anthc-), pyrene-1-carboxyl-ate (pyrc-), phthalate, (ph2-), isophthalate (iph 2-), terephthalate (tph2-), 2,5-dihydroxy-1,4- benzenediacetate (dihyac2-) and, 1,3,5-benzenetricarboxylate (btc3-)) and three herbicides (4-amino-3,5,6-trichloropyridine-2- carbox-ylate (ATCP-), dichlorophenoxyacetate (2,4-D-) and glyphosate (PMG2-)) in water solution. The [30]phen2N 6 receptor was found to be the most suitable for binding the anions considered in a 1:1 stoichiometry. The three receptors exhibit a remarkable binding selectivity towards the extended aromatic anion pyre- at low pH values. Their binding affinities for the monocarboxylate anions decrease with the extension of the aromatic system in the order pyre- > anthc- > naphc- > bzc-, which indicates the presence of π-π stacking interactions in the molecular recognition of these anions. Molecular dynamics simulations carried out for the binding of (H4[30]phen2N6}4+ and {H 6Me2[34]phen2N6}6+ with pyre-, anthc-, naphc-, iph2- and btc3- in water showed that these receptors adopt a folded conformation with the anion inserted between the two phen heads and that the molecular recognition is governed by π-π stacking interactions and multiple N-H...O=C hydrogen bonds. The binding free energies estimated theoretically are very similar to those found by Potentiometric methods, which supports the proposed binding arrangement.
- Cruz, Carla,Cahsto, Vania,Delgado, Rita,Felix, Vitor
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supporting information; scheme or table
p. 3277 - 3289
(2009/12/05)
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- Colorant compounds, intermediates, and compositions
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Colorants are disclosed that exhibit high color strength, bright shades, and high thermal stability. Such compounds have found application as colorants for polyethylene terephthalate (“PET”). Potential end uses include disperse dyes, non-warping pigments, decolorizable colorants, and the like. Compounds and methods for synthesis include benzodifuranone related compounds, benzene centered lactones, benzene centered lactams; benzene-centered thiolactones; naphthalene-centered lactones; naphthalene-centered lactams; naphthalene-centered thiolactones; anthraquinone-centered lactones; anthraquinone-centered lactams; anthraquinone-centered thiolactones; anthracene-centered lactones; anthracene-centered lactams; anthracene-centered thiolactones; hetero-aromatic-centered lactones; hetero-aromatic centered lactams and hetero-aromatic centered thiolactone compounds, and the like. Furthermore, resins such as PET or other polymeric resins containing the compounds are disclosed.
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Page/Page column 6
(2010/11/24)
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