EFFECT OF CHLORIDE IONS ON THE STRUCTURAL, OPTICAL, MORPHOLOGICAL, AND ELECTROCHEMICAL PROPERTIES OF Cu2O FILMS ELECTRODEPOSITED ON FLUORINE-DOPED TIN OXIDE SUBSTRATE FROM A DMSO SOLUTION

This study shows the results attained during the electrodeposition of Cu2O films on fluorine-doped tin oxide (FTO) substrate from a dimethyl sulfoxide (DMSO) solution in the presence of chloride ions. Before the film electrodeposition and in order to establish the best conditions for the Cu2O electrodeposition, a detailed electrochemical study of the precursors in the presence of chloride ions was performed. The voltammetric profiles obtained show significant differences compared to those previously obtained during the study of the Cu2O electrodeposition from a free-chloride DMSO solution. These differences are the result of the coordination complexes formation between chloride ions and the different copper species in solution. The films were potentiostatically electrodeposited between -1.4 V and -1.6 V vs Ag/AgCl(sat) reference electrode. Then, these films were characterized through different techniques: X-ray diffraction, scanning electron microscopy, optical characterization, and capacitance measurements through electrochemical impedance spectroscopy.