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Overoxidized polypyrrole films templated with L-glutamate have been utilized for enantioselective detection of L- and D-glutamic acid. Various important fabrication factors controlling the performance of the overoxidized polypyrrole films have been investigated using fluorescence spectrometry in conjugation with the electrochemical quartz crystal microbalance technique. The measured fluorescence intensity was related to the concentration of glutamate taken up into the films. It was found that L-glutamate was inserted approximately 30 times higher into the film than D-glutamate. Several key parameters such as applied potential and pH of amino acid solution were varied to achieve the optimum sensor response. The sensor templated with L-glutamic acid also exhibited excellent selectivity over several other L- and D-amino acids. Higher enantioselectivity of overoxidized polypyrrole film than that for previously reported imprinted polymers can be attributed to the potential-induced uptake/release of targeted molecules.

A silver molecular ink platform formulated for screen, inkjet, and aerosol jet printing is presented. A simple formulation comprising silver neodecanoate, ethyl cellulose, and solvent provides improved performance versus that of established inks, yet with improved economics. Thin, screen-printed traces with exceptional electrical (<10 mΩ/□/mil or 12 μΩ·cm) and mechanical properties are achieved following thermal or photonic sintering, the latter having never been demonstrated for silver-salt-based inks. Low surface roughness, submicron thicknesses, and line widths as narrow as 41 μm outperform commercial ink benchmarks based on flakes or nanoparticles. These traces are mechanically robust to flexing and creasing (less than 10% change in resistance) and bind strongly to epoxy-based adhesives. Thin traces are remarkably conformal, enabling fully printed metal-insulator-metal band-pass filters. The versatility of the molecular ink platform enables an aerosol jet-compatible ink that yields conductive features on glass with 2× bulk resistivity and strong adhesion to various plastic substrates. An inkjet formulation is also used to print top source/drain contacts and demonstrate printed high-mobility thin film transistors (TFTs) based on semiconducting single-walled carbon nanotubes. TFTs with mobility values of ∼25 cm V s and current on/off ratios >10 were obtained, performance similar to that of evaporated metal contacts in analogous devices.

Copper formate complexes with various primary amines, secondary amines and pyridines were prepared, and their decomposition into conductive films was characterized. A comparison of the various complexes reveals that the temperature of thermolysis depends on the number of hydrogen bonds that can be formed between the amine and formate ligands. The particle size resulting from sintering of the copper complexes is shown to depend on the fraction of amine ligand released during the thermolysis reaction. The particle size in turn is shown to govern the electrical properties of the copper films. Correlations between the properties of the amines, such as boiling point and coordination strength, with the morphology and electrical performance of the copper films were established and provide a basis for the molecular design of copper formate molecular inks.

A novel strategy for the synthesis of a substituted polyaniline that can be switched between a self-doped and non-self-doped state is presented. The approach uses the complexation between boronic acid-substituted aniline, a diol (d-fructose), and fluoride to generate an anionic monomer. Under these conditions, chemical polymerization results in a self-doped, water-soluble, conducting polyaniline under neutral aqueous conditions. The self-doped polymer can be simply and reversibly converted to an insoluble non-self-doped form by reducing the concentration of fluoride. Characteristics of the polymerization reaction and the resulting polymer are discussed.