Electrochemical Synthesis and Characterization of Zinc Sulfide (zns) Semiconducting Thin Films from Citrate-Based Plating Bath

The primary purpose of this article is to synthesize electrochemically a binary semiconductor material ZnS that is generally used for manufacturing solar cells. It has been shown that the properties and composition of the deposits are closely linked to the synthesis conditions, namely the applied potential, the electrolyte concentration and its composition. The electrodeposition was realized from an acidic medium with a pH ranging from 3.5 to 4.5 and containing respectively 0.02 M of zinc chloride (ZnCl2), 0.02 M of sodium thiosulphate (Na2S2O3), and 0.15 M of trisodium citrate (Na3C6H5O7) as complexing agent. The deposition mechanism of ZnS binary alloys was investigated using various electrochemical techniques. ZnS thin films were electrochemically deposited on a tin-doped indium oxide (ITO) substrate in one single step, at a potential of −1 V/SCE. The effects of the concentration ratio ([zinc]/[sulfur]) on the electrochemical, optical, and compositional properties of thin films as well as their surface morphology were also investigated.