Electrochemical synthesis of hexagonal hollow ZnO nanostructures

Abstract

[EN] A simple and controllable one-step electrodeposition process is proposed in order to obtain ZnO nanotubes. Zinc oxide thin films were grown on fluorine-doped tin oxide by electrodeposition from an aqueous electrolyte containing zinc nitrate and potassium nitrate. Generally, in aqueous electrolytes ZnO is electrochemically deposited in the form of hexagonal nanocolumns. These nanocolumns grow perpendicularly to the substrate until reaching a maximum height of about 2 µm and then the perpendicular growth vanishes and the solid nanocolumns develop to hexagonal hollow structures. Several characteristics of the electrodeposited films such as thickness, morphology and crystalline structure were obtained as a function of the deposited charge. The evolution of the morphology of the electrodeposited layers as a function of time was monitored by Scanning Electron Microscopy. X-Ray Diffraction confirms that hexagonal nanotubes are preferentially oriented along the (002) direction.