Synthesis of zinc oxide thin film by anodizing

Abstract

In this work, 99% purity zinc plates were anodized at potentiostatic conditions in distilled water at 25°C. The anodizing voltages were varied from 10 V to 30 V. The morphologies of the ZnO thin film were investigated by using scanning electron microscope (SEM) and the compositions were confirmed through the characterization using X-ray diffraction (XRD). The current versus time transients during the anodizing were recorded. SEM images show that thread-like nanostructures were present on the surface of Zn plates anodized at 25 V and 30 V. XRD patterns revealed that ZnO were present on all Zn plates anodized at anodizing voltages ranged from 10 V to 30 V. Current recorded during the anodizing process increased with the anodizing voltages due to the formation of thread-like nanostructures with lower electrical resistance.

Anodization fabrication techniques and energy-related applications for nanostructured anodic films on transition metals

“…Several reports have mentioned that, in oxalic acid electrolytes, nanoporous ZnO thin films were typically formed by the electrochemical anodization of Zn [173,174] . Interestingly, ZnO porous structures on Zn metal were also obtained by Zn anodization just using deionized/distilled water as an electrolyte at room temperature [175,176] . As the deionized water itself was slightly acidic (pH 5.8), the Zn anodization could be carried out in water without the need for the addition of any extra electrolyte [175] .…”

“…Interestingly, ZnO porous structures on Zn metal were also obtained by Zn anodization just using deionized/distilled water as an electrolyte at room temperature [175,176] . As the deionized water itself was slightly acidic (pH 5.8), the Zn anodization could be carried out in water without the need for the addition of any extra electrolyte [175] . The morphologies of the ZnO thin films were found to be highly dependent on the anodization voltages [176] .…”