Selective oxidation of ω-tertiary amine self-assembled thiol monolayers to tertiary amine N-oxides is shown to transform the adhesion of model proteins lysozyme and fibrinogen upon them. Efficient preparation of both secondary and tertiary linker amides as judged by X-ray photoelectron spectroscopy (XPS) and water droplet contact angle was achieved with an improved amide bond formation on gold quartz crystal microbalance (QCM) sensors using 2-(1H-7-azabenzotriazol-1-yl)-1,1,3,3-tetramethyl hexafluorophosphate methanaminium uronium (HATU). Oxidation with hydrogen peroxide was similarly assessed, and adhesion of lysozyme and fibrinogen from phosphate buffered saline was then assayed by QCM and imaged by AFM.
View Article and Find Full Text PDFACS Appl Mater Interfaces
November 2012
The fabrication, exceptional properties, and application of 8 nm thick Cu, Ag, Au, and Cu/Ag bilayer electrodes on flexible polyethylene terephthalate (PET) and polyethylene naphthalate (PEN) substrates is reported. These electrodes are fabricated using a solvent free process in which the plastic surface is chemically modified with a molecular monolayer of thiol and amine terminated alkylsilanes prior to metal deposition. The resulting electrodes have a sheet resistance of ≤14 Ω sq⁻¹, are exceptionally robust and can be rapidly thermally annealed at 200 °C to reduce their sheet resistance to ≤9 Ω sq⁻¹.
View Article and Find Full Text PDFA low-cost window electrode for organic photovoltaics that simultaneously removes the requirement for conducting oxide and conventional low work function electrodes and functions as a sink for oxygen/water in the heart of the device. Remarkably the functionality of this electrode, which is based on a 7.8 nm nanostructured Cu:Al film, improves upon in situ oxidation as demonstrated in bulk heterojunction organic photovoltaics.
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