Modification of polyamide-CdS-CdSe composite material films with Ag using a cation-cation exchange reaction

Thin mixed CdSe-CdS-Ag2Se-Ag2S films were deposited on a polyamide 6 (PA) surface by successfully using a cation-exchange reaction between Cd2+ and Ag+ to convert CdSe-CdS into Ag2Se-Ag2S. These were deposited using a K2SeS2O6 precursor solution at 60 °C followed by cadmium acetate (Cd(CH3COO)2). An aqueous AgNO3 solution was used as the Ag source. XRD patterns showed a complex PA-Cd-S-Se-Ag film crystalline composition with CdS, CdSe, Ag2S and Ag2Se peaks. Calculated dislocation density ranged within 5-15 × 1013 lines·m−2 indicating high quality atomic layers. Atomic Absorption Spectroscopy (AAS) showed five- to ten-fold excess of chalcogens to metals in the thin films formed. No chalcogenides were observed on the sample surface during XPS analysis after Ag exchange due to the desorption of CdS and CdSe layers, not diffused into the bulk of the polymer suggesting that silver chalcogenides were located subsurface, as opposed to the outermost layer, likely comprised of Ag2O.