Non-aqueous cathodic electrodeposition of large scale uniform ZnO and CdO nanowire arrays

Abstract

We fabricated ordered ZnO and nanowire arrays in anodic alumina membrane (AAM) by cathodic electrodeposition from a non-aqueous dimethylsulfoxide (DMSO) bath containing zinc chloride and dissolved oxygen. X-ray diffraction (XRD), high-resolution transmission electron microcsopy (HRTEM), and electron diffraction (ED) show that the ZnO nanowires are well crystallized with wurtzite structure. The morphologies and structure of the ZnO nanowires have been characterized by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The results demonstrate that the ZnO nanowires with diameters of about 60nm are uniformly embedded into the hexagonally ordered nanopores of anodic alumina membrane. A sharp ultraviolet emission at 383nm and visible broad emission bands around 592nm were observed from ZnO nanowire arrays. They originated from the near-band emission due to the recombination of bound excitons and deep level emission due to defects, respectively. The cathodic electrodeposition technique in DMSO is also extended to synthesize CdO nanowire arrays.