100 research outputs found
Polyaniline coated conducting fabrics : chemical and electrochemical characterization
Polyaniline coated conducting fabrics have been obtained by chemical oxidation of aniline by potassium peroxydisulfate on polyester fabrics. Two different acids have been employed to carry out the synthesis (HCl and H2SO4), obtaining the best results of conductivity with the latter one. The conducting fabrics have been characterized chemically by means of Fourier transform infrared spectroscopy with attenuated total reflection (FTIR-ATR), energy dispersive X-Ray (EDX) and X-ray photoelectron spectroscopy (XPS). The morphology of the coatings has been observed by means of scanning electron microscopy (SEM). The conducting properties of the fabrics have been measured by means of electrochemical impedance spectroscopy (EIS). The electrochemical characterization has been carried out by means of cyclic voltammetry (CV) and scanning electrochemical microscopy (SECM). The conducting fabrics have also shown electrochromic properties, changing its color from green yellowish at −1 V to dark green at +2 V. The durability of the coating has been evaluated by means of washing and rubbing fastness tests.Authors thank to the Spanish Ministerio de Ciencia e Innovacion and European Union Funds (FEDER) (contract CTM2010-18842-C02-02) and Universitat Politecnica de Valencia (Primeros Proyectos de Investigacion (PAID-06-10)) for the financial support. J. Molina is grateful to the Conselleria d'Educacio (Generalitat Valenciana) for the FPI fellowship
Catalyst preparation for CMOS-compatible silicon nanowire synthesis
Metallic contamination was key to the discovery of semiconductor nanowires,
but today it stands in the way of their adoption by the semiconductor industry.
This is because many of the metallic catalysts required for nanowire growth are
not compatible with standard CMOS (complementary metal oxide semiconductor)
fabrication processes. Nanowire synthesis with those metals which are CMOS
compatible, such as aluminium and copper, necessitate temperatures higher than
450 C, which is the maximum temperature allowed in CMOS processing. Here, we
demonstrate that the synthesis temperature of silicon nanowires using copper
based catalysts is limited by catalyst preparation. We show that the
appropriate catalyst can be produced by chemical means at temperatures as low
as 400 C. This is achieved by oxidizing the catalyst precursor, contradicting
the accepted wisdom that oxygen prevents metal-catalyzed nanowire growth. By
simultaneously solving material compatibility and temperature issues, this
catalyst synthesis could represent an important step towards real-world
applications of semiconductor nanowires.Comment: Supplementary video can be downloaded on Nature Nanotechnology
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First report of Lymnaea cousini Jousseaume, 1887 naturally infected with Fasciola hepatica (Linnaeus, 1758) (Trematoda: Digenea) in Machachi, Ecuador
Desenvolvimento de membranas e filmes auto-suportados a partir de polianilina: síntese, caracterização e aplicação
XXXI.— A brief bibliographical Résumé of the Erythræan Molluscan fauna, with descriptions of sixteen species from Aden
Voltage-induced recovery of dielectric breakdown (high current resistance switching) in HfO2
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Hybrid organic-inorganic copolymers based on oxo-hydroxo organotin nanobuilding blocks
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Chemical state of Ag in Conducting Bridge Random Access Memory cells: a depth resolved X-ray Absorption Spectroscopy investigation
International audienceConducting Bridge Random Access Memories (CBRAM) are a promising substitute for FLASH technology but problems with limited retention of the low resistance ON state still hamper their massive deployment. Depth resolved X-ray Absorption Spectroscopy has been used to describe the chemical state of the atoms of the active electrode (in this case Ag) and to reveal the role of Sb as stabilizer of the metallic stat
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