No abstract

International audienceA facile and rapid localized electrochemical reduction of colloid copper particles is proposed using the scanning electrochemical,microscope (SECM), technique. In this purpose, thin films of composite silica :glass containing copper salts were prepared by the sol-gel method via the dip coating technique. Acid-catalyzed tetraethylorthosilane (TEOS) solutions charged with copper nitrate were used as precursors. This one-pot experiment can be performed in mild conditions. The localized generation of copper metallic nanostructures on silica film has been performed by electroreduction of methyl viologen on an ultramicroelectrode (UME). The UME generates reducing species, which in turn diffuse:toward the silica matrix and reduce the metal ions. The diameter of the working electrode and the electrolysis period Were taken into account to study the size of the generated dotted micropatterns. The compositions of the modified silica films were characterized by X-ray diffraction (XRD), scanning,electronic microscopy (SEM), optical microscopy,, and vibrational (IR-ATR and Raman) and X-ray photoelectron spectroscopies (XPS)

The complex of Al (111) with paracetamol have synthesized and characterized using UV–Vis, Infrared spectroscopies and melting point. The ligand has been found to behave as tridentate chelating agents. Paracetamol complex coordinate through the carboxylate oxygen, phenolate oxygen atom, and amine group. The complex solubility was evaluated for several solvents and it was found the compound was more soluble in DMSO. Job’s method of continuous variation suggested 1 : 2 metals to ligand stoichiometry for paracetamol complex

The luminescent alkoxysilyl-functionalized fluorenone (N-(9-N-fluorenimine)-N’-(triethoxysilanepropyl) urea) has been synthesized to chelate specifically halide ions via hydrogen bonding of the fluorenimine moiety. Based on the propensity of siloxanes to form electrodeposited films, we examined the electrochemical behavior of this alkoxysilyl functionalized fluorenone on gold electrode in THF-based electrolyte. In the presence of water traces, quartz crystal microbalance coupled with cyclic voltammetry underlines the electrocatalyzed surface-condensation of the molecule occurring on the electrode surface in cathodic reduction. Scanning electrochemical microscopy allows to perform localized electrodeposition in the feedback mode. Epitaxially and PVD-grown polycrystalline gold surfaces were used for topography observations by STM and spectroscopic characterizations of the resulting coating. Finally, spectrofluorometry was carried out specifically for sensing halide ions chelated by the alkoxysilyl fluorenone-based mono-layer electrodeposited on the electrode surface.