Preparation and characteristics of CdS thin films by dip-coating method using its nanocrystal ink

CdS nanocrystals were synthesized by hot injection method using EG as solvent, polyvinylpyrrolidone as dispersant, triethanolamine as stabilizing agent, Cd(NO3)2·4H2O and H2NCSNH2 as cadmium and sulfur sources respectively. The synthesized nanocrystals were washed and ultrasonically dispersed with absolute ethanol to prepare nanocrystal ink. CdS thin films were deposited by dip-coating glass substrates with the nanocrystal ink and annealed at 450 °C in Ar atmosphere. Crystalline phase, morphology and element stoichiometry of the CdS nanocrystals derived from different synthesis temperatures were investigated by XRD, TEM and EDS. Surface morphology, crystalline phase and optical absorption spectrum of the CdS films were characterized by SEM, XRD and UV–Vis.