Electrochemical deposition of Zinc Oxide thin film using two-terminal setup

Abstract

This paper reports on deposition process of Zinc Oxide (ZnO) using a simple electrochemical approach. The ZnO thin film was deposited on the Aluminium (Al) substrate in an aqueous solution of Zinc Chloride (ZnCl2) at room temperature using two terminals electrochemical cell that consisted of positive and negative electrodes. Two types of Al substrate were used, which are Al foil and Al plate. Al foil or Al plate acted as the negative electrode (cathode) while Platinum (Pt) wire or Zinc (Zn) plate as the positive electrode (anode). A constant current density of 10 A/m2 was applied in the experiment. 5mM ZnCh and 0.1M potassium chloride (KCl) support solution used as the electrolytic solution. The experiment was carried out by varying the concentration of ZnCl2 electrolyte solution and KCl supporting solution. Three different mixture of electrolyte solution and supporting solution, 125 ml of ZnCl2 + 25 ml of KCl, 100 ml of ZnCl2 + 50 ml KCl and lastly 75 ml ZnCl2 + 75 ml KCl, were used. Each of the samples underwent 30 minutes of deposition process. At the end of the experiment, the morphologies and properties of ZnO were determined by studying the result from Single Electron Microscope (SEM) and Energy Dispersive X-ray spectroscopy (EDX). The structures of the ZnO were found as nanosheet-like network. The results evinced the potential of utilizing simpler setup of electrochemical approach in producing good characteristic of ZnO film for respective applications such as solar cell.