Well ordered Hollow Urchin-like ZnO by Electrodeposition

Increasing the aspect ratio of ZnO nanostructures is one possible strategy to improve their physical properties. ZnO nanostructures with 1D and 3D morphologies were obtained using electrochemical deposition. Playing with various deposition parameters enabled to obtain arrays of vertically aligned ZnO nanowires (NWs) with controlled dimensions, density and electrical properties. The concentrations of zinc or chloride ions in the solution were found to be major parameters to monitor them. ZnO-NWs were transformed into nanotubes (NTs) with an increased aspect ratio compared to the NWs, by selectively dissolving the core of the ZnO-NWs in a highly concentrated KCl solution. The aspect ratio was strongly increased, when the ZnO-NWs were hierarchically organized into 3-D morphology. The synthesis of thin films composed of ordered hollow urchin-like ZnO-NWs was performed by combining the electrochemical deposition and a polystyrene sphere template