Thermodynamic Stability and Interfacial Reactions of CdS, ZnS and Cd_1-xZn_xS in Aqueous Solution

Abstract

This study is devoted to understanding the thermodynamic basis of the process of synthesis of ZnS, CdS and their solid solutions in aqueous solutions in order to obtain thin films of required composition. The typical interfacial reactions were considered, and the thermodynamic calculations of the possible redox reactions and the reaction standard electrode potentials have been done. The composition of a solution is analyzed by means of thermodynamic diagrams as a function of redox potential versus pH. It has been demonstrated that the near-surface layer with the defect structure and the excess of sulfur on a surface can be formed in case of ZnS at pH < 1.5 during the synthesis. The application of obtained data in the synthesis of semiconducting materials is also shown.