Sono and electrochemical synthesis and characterization of copper core-silver shell nanoparticles.

Cu-Ag core-shell nanopowders have been prepared by ultrasound-assisted electrochemistry followed by a displacement reaction. The composition of the particles has been determined by X-ray diffraction (XRD) and energy dispersive X-ray spectroscopy (EDX). The XRD patterns versus time displacement show that higher are the silver peaks intensities, weaker are the copper ones.

Template assisted electrodeposition of germanium and silicon nanowires in an ionic liquid.

In this paper we report for the first time on the room temperature template synthesis of germanium and silicon nanowires by potentiostatic electrochemical deposition from the air- and water stable ionic liquid 1-butyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)amide ([Py(1,4)]Tf(2)N) containing GeCl(4) and SiCl(4) as a Ge and Si source, respectively. Commercially-available track-etched polycarbonate membranes (PC) with an average nominal pore diameter of 90-400 nm were used as templates. Ge and Si nanowires with an average diameter corresponding to the nanopores' diameter and lengths of a few micrometres were reproducibly obtained.

Growth of silicon nanowires of controlled diameters by electrodeposition in ionic liquid at room temperature.

Silicon nanowires were fabricated for the first time by electrochemical template synthesis at room temperature. This innovative, cheap, and simple process consists of electroreduction of Si ions using a nonaqueous solvent and insulating nanoporous membranes with average pore diameters from 400 to 15 nm which fix the nanowires diameters. Characterization techniques such as scanning and transmission electron microscopies, infrared absorption measurements, X-ray diffraction experiments, energy dispersive X-ray, and Raman spectrometries show that the as-deposited silicon nanowires are amorphous, composed of pure Si and homogeneous in sizes with average diameters and lengths well matching with the nanopores' diameters and the thicknesses of the membranes.

Study of copper electroless displacement by Ag+; prospecting for multilayers elaboration.

The copper electroless displacement by silver has been studied in the absence of cyanide ions. The investigations have been carried out using a quartz crystal microbalance, and it was shown that the electroless displacement was plainly diffusion-controlled during 1 min. The electrochemical deposition of Cu-Ag multilayers has been achieved using two methods: by displacement reaction and by alternated applied potentials.