A Study of Ni & Cu Surface Status in a Supercritical Carbon Dioxide into a Microemulsion Using QCM

A set of Quartz Crystal Microbalances (QCM's) was used to observe the film removal characteristics of three different CO2-nitric acid microemulsions. QCM's electroplated with nickel or copper were used as specimens. F-AOT, NP-4 and the synthesized Proline Surfactant-1 were used as surfactants to create microemulsions. While the F-AOT microemulsion yielded a relatively low removal rate, that of the Proline Surfactant-1 completely removed the Cu metal film within a short period of time. The NP-4 microemulsion removed the metal surface. However, removal rate measurements per QCM were not possible due to the instability of the microemulsion when Cu ions were present in the nitric solution. The reaction kinetics and metal removal capabilities of microemulsion formed by the different surfactants are explained along with the characteristics of reverse micelles.