One-step template-free electrosynthesis of 300 μm long copper sulfide nanowires

We report a one-step template-free electrosynthesis method for high-aspect-ratio copper sulfide nanowires from dilute copper solution containing thiourea on platinum and stainless steel surfaces. Fast pulse electrodeposition produced a deposit composed of copper sulfide nanowires with Cu to S at% ratios of ca. 1, lengths up to 300 μm, and diameters between 40 and 600 nm, depending on the deposition conditions. The main part of the deposit was found to be amorphous. Crucial parameters that decide the dimensions are thiourea and copper ion concentrations, potential, and the on–off cycle time of the pulse electrodeposition process. A nanowire growth mechanism which accounts for these parameters is also proposed.