Template electrosynthesis of aligned Cu2O nanowires Part I. Fabrication and characterization

Abstract

Large arrays of aligned copper oxide nanowires were produced by electrodeposition, using anodic alumina membranes as template. We have studied the effect of two fundamental parameters involved in fabrication process: potential perturbation and bath composition. Performing electrodeposition from a copper acetate/sodium acetate bath (pH 6.5), we found that chemical composition of nanowires varied in dependence on the shape of the applied potential perturbation: pure copper oxide nanowires were produced by pulsed potential, whilst continuous electrodeposition resulted in a co-deposition of Cu and Cu2O. In a copper lactate bath, buffered at pH 10, the shape of perturbation did not influence the chemical composition of nanowires, consisting of pure copper oxide. Besides, bath composition influenced the crystallographic structure of nanowires: in the acetate bath polycrystalline nanowires, having a maximum length of about 2.5m,were obtained whilst in the lactate electrolyte Cu2O nanowires with a preferential orientation along the (2 0 0) plane were deposited. In every case, nanowire diameters were uniform with an average value of about 200 nm. Growth rate of nanowires was influenced by the shape of potential pulse.