References of "Wislez, Arnaud"
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See detailLow bandgap copolymers based on monofluorinated isoindigo towards efficient polymer solar cells
Tomassetti, Mirco ULg; Ouhib, Farid ULg; Wislez, Arnaud ULg et al

in Polymer Chemistry (2015), 6(33), 6040-6049

To explore the effectiveness of monofluorinated isoindigo as an electron-deficient building block in push–pull conjugated polymers for organic solar cell applications, four low bandgap copolymers are ... [more ▼]

To explore the effectiveness of monofluorinated isoindigo as an electron-deficient building block in push–pull conjugated polymers for organic solar cell applications, four low bandgap copolymers are effectively synthesized and characterized. The effects of fluorine introduction, thiophene spacer length and polymer molar mass on the general electro-optical polymer characteristics, thin film blend micro- structure and electronic performance are investigated. Isoindigo monofluorination effectively improves the power conversion efficiency from 2.8 up to 5.0% upon molar mass optimization, without using any processing additives or post-treatments. [less ▲]

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See detailLinear and propeller-like fluoro-isoindigo based donor–acceptor small molecules for organic solar cells
Ouhib, Farid ULg; Tomassetti, Mirco ULg; Dierckx, Wauter et al

in Organic Electronics (2015), 20

Two donor–acceptor type fluoro-isoindigo based small molecule semiconductors are syn- thesized and their optical, electrochemical, thermal, and charge transport properties are investigated. The two ... [more ▼]

Two donor–acceptor type fluoro-isoindigo based small molecule semiconductors are syn- thesized and their optical, electrochemical, thermal, and charge transport properties are investigated. The two molecular chromophores differ by their architecture, linear (M1) vs propeller-like (M2). Both molecules present a broad absorption in the visible range and a low optical HOMO–LUMO gap (?1.6 eV). AFM images of solution-processed thin films show that the trigonal molecule M2 forms highly oriented fibrils after a few seconds of solvent vapor annealing. The materials are evaluated as electron donor components in bulk heterojunction organic solar cells using PC61BM as the electron acceptor. The devices based on the propeller-like molecule M2 exhibit a high open-circuit voltage (around 1.0 V) and a power conversion efficiency of 2.23%. [less ▲]

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See detailUnraveling the complexity of the interactions of DNA nucleotides with gold by single molecule force spectroscopy
Bano, Fouzia; Sluysmans, Damien ULg; Wislez, Arnaud ULg et al

in Nanoscale (2015), 7

Addressing the effect of different environmental factors on the adsorption of DNA to solid supports is critical for the development of robust miniaturized devices for applications ranging from biosensors ... [more ▼]

Addressing the effect of different environmental factors on the adsorption of DNA to solid supports is critical for the development of robust miniaturized devices for applications ranging from biosensors to next generation molecular technology. Most of the time, thiol-based chemistry is used to anchor DNA on gold – a substrate commonly used in nanotechnology – and little is known about the direct interaction between DNA and gold. So far there have been no systematic studies on the direct adsorption behavior of the deoxyribonucleotides (i.e., a nitrogenous base, a deoxyribose sugar, and a phosphate group) and on the factors that govern the DNA–gold bond strength. Here, using single molecule force spectroscopy, we investigated the interaction of the four individual nucleotides, adenine, guanine, cytosine, and thymine, with gold. Experiments were performed in three salinity conditions and two surface dwell times to reveal the factors that influence nucleotide–Au bond strength. Force data show that, at physiological ionic strength, adenine–Au interactions are stronger, asymmetrical and independent of surface dwell time as compared to cytosine–Au and guanine–Au interactions. We suggest that in these conditions only adenine is able to chemisorb on gold. A decrease of the ionic strength significantly increases the bond strength for all nucleotides. We show that moderate ionic strength along with longer surface dwell period suggest weak chemisorption also for cytosine and guanine. [less ▲]

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See detailSINGLE-MOLECULE AFM STUDY OF ADHESIVE POLYMERS PREPARED BY COBALT-MEDIATED RADICAL POLYMERIZATION AND NITRONE-MEDIATED RADICAL COUPLING
Willet, Nicolas ULg; Sluysmans, Damien ULg; Delvaux, Cédric ULg et al

Scientific conference (2012, September 10)

Well-defined poly(vinyl acetate) (PVAc) chains prepared by CMRP (cobalt-mediated radical polymerization) were coupled using an alkyne-functional nitrone via NMRC (nitrone-mediated radical coupling).1 In ... [more ▼]

Well-defined poly(vinyl acetate) (PVAc) chains prepared by CMRP (cobalt-mediated radical polymerization) were coupled using an alkyne-functional nitrone via NMRC (nitrone-mediated radical coupling).1 In all the cases, the coupling efficiencies were close to 90% or higher. The polymers mid-chain functionalized with an alkyne group were then reacted with azide-functionalized atomic force microscopy (AFM) tips via copper-catalyzed azide-alkyne cycloaddition (CuAAC). As a result, polymers having a double-branch architecture were linked to AFM tips via a short linker. The structure and the molecular parameters of the polymers were determined by NMR and GPC, whereas the ‘click’ step onto AFM tips was assessed by performing the same CuAAC reaction onto macroscopic surfaces and characterizing them by ATR FT-IR. The adhesive properties of these double-branched polymers were studied by AFM single-molecule force spectroscopy. By performing approach-retraction cycles in solution upon a glass surface, the interaction between single PVAc chains and the surface was investigated. The effect of the double-branch architecture on the adhesion forces was under focus. Setting a residence time of the tip on the surface before retraction was found to have a beneficial influence on the adhesion forces. Signs of multiple interactions acting in parallel were detected in the experimental force-distance traces. [less ▲]

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See detailMolecular biomimetics applied to medical devices
Van de Weerdt, Cécile ULg; Archembeau, Catherine; Vreuls, Christelle ULg et al

Poster (2012, May 05)

Detailed reference viewed: 68 (21 ULg)