Electrodeposition of Silver–Graphene Films for Electronic Connectors in Succinimide Solutions

Silver is electroplated on the surface of connectors as a protective barrier layer in order to improve the corrosion resistance and to increase the durability of the connector. In this work, silver-graphene films were electrodeposited on copper–zinc alloy substrates from a succinimide silver-plating system in Hull-cell alkaline solutions by the addition of 0.4 g L –1 graphene oxide. The crystallographic structure and microstructure of the formed films were determined by X-ray diffraction and scanning electron microscopy, respectively. The corrosion resistance of the films was measured by a potentiodynamic polarization test. The results show that a low amount of graphene was incorporated into a silver deposit. The addition of graphene oxide could not influence the deposition rate and the crystallographic structure of the film, but resulted in a decrease in the size of aggregates or particles, compared with those of a pure silver film. The optimal current density was found to be 0.5 ~ 1.0 A dm –2 , the surface of the films had a homogeneous close-packed fine-crystalline structure. The films were uniform, dense, and adherent to the substrate, without any evidence of delamination. At the same time, the addition of graphene oxide improved the corrosion resistance of silver films to a certain extent.