Date of Award

Fall 2013

Project Type


Program or Major

Chemical Engineering

Degree Name

Master of Science

First Advisor

Dale P Barkey


Potential oscillations during copper electrodeposition on a rotating disk electrode (RDE) in acidic-sulfate solution with leveler and an accelerant were investigated. Potential oscillations were observed in the presence of accelerant Bis-(3-sulfopropyl)-disulfide (SPS) and the levelers Enthone L76, a commercial leveler, and Janus green B. In the L76/SPS system, the period and amplitude of oscillation were affected by the concentrations of SPS and leveler, RDE rotation speed and the current density. Within a specific concentration range, higher SPS concentration enhanced the potential oscillation and higher leveler concentration weakened the potential oscillation. Potential oscillation was observed in a certain current density range and the oscillation was enhanced by higher current density. Higher RDE rotation speed promoted the potential oscillation at rotating speeds less than 500 rpm.

In the JGB and SPS system, the potential oscillation was affected by the concentration of SPS and JGB, current density, rotation speed and the presence of oxygen, but no clear trends were determined. A mechanism is proposed which relates potential dependent desorption and adsorption of the additives to the observed oscillation.