Electrodeposition of Silver(I) Selenide from Aqueous Solutions of Thiocyanates

Silver(I) selenide that exhibits pronounced thermoelectric properties is electrodeposited from aqueous solutions containing thiocyanate complexes of silver(I) and Se(IV) compounds at pH 4.7. Ag2Se is formed at the cathodic potential more negative than -0.9 V (SHE). The coatings are characterized by the methods of scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), and atomic-force microscopy (AFM). The stoichiometry of the cathodic deposit is close to Ag2Se. XRD studies demonstrated the formation of the orthorhombic modification of silver(I) selenide under electrodeposition conditions. The cathodic deposits have the columnar nanostructure.