Characterization of CdxTeyOz/CdS/ZnO Heterostructures Synthesized by the SILAR Method

Abstract

CdxTeyOz/CdS/ZnO heterostructures were obtained by the SILAR method using ionic electrolytes. A CdS film was formed as a buffer layer for better adhesion of the cadmium-tellurium oxides to the substrate surface. In turn, the ZnO substrate was previously prepared by electrochemical etching to form a rough textured surface. In addition, an annealing mode was used in an oxygen stream to complete the oxidation process of the heterostructure surface. The resulting nanocomposite was investigated using RAMAN, XRD, SEM, and EDX methods. We assume that the oxides CdO and TeO4 initially form on the surface and later evolve into TeO2 and TeO3 when saturated with oxygen. These oxides, in turn, are the components of the ternary oxides CdTeO3 and CdTe3O8. It should be noted that this mechanism has not been fully studied and requires further research. However, the results presented in this article make it possible to systematize the data and experimental observations regarding the formation of cadmium-tellurium films.