Executive Summary : | This study aims to understand the underlying chemical changes in transient potential oscillatory patterns of self-organized electrochemical systems, particularly metal electrodeposition. The complexity of these systems is increased by local interactions, such as self-organization. The potential oscillatory behavior of galvanostatic electroplating systems is typically attributed to the reaction of precursors on the substrate and diffusion of reactant/by-products from/to the electrolyte. The presence of organic additives further complicates the system. Two distinct oscillatory potential patterns in cobalt electrodeposition were observed in the presence of 1,4-Butynediol additive, which are associated with cyclical chemical changes in the cobalt film and additive, ultimately determining the morphology of the film. In-situ spectroelectrochemical studies provide real-time information of chemical changes upon electrical stimulation or vice versa at the interface. The study will use interference-free Shell-isolated Nanoparticle-enhanced Raman Spectroscopy (SHINERS) to assess operando chemical changes in the deposited film and organic additives, while quasi-operando tip-enhanced Raman spectroscopy (TERS) will determine the trend in lateral chemical distribution over the oscillation. The proposed research will enable deeper understanding of intermediate events, facilitating the development of new methodologies and additives in the metal plating and finishing market. |