Short Assessment on Thin film ElectrodesAuthor(s): Elizabeth Cooper
Anodic stripping voltammetry (ASV) is a strong electrochemical analytical method for detecting and quantifying a wide range of metal ion species in aqueous fluids at extremely low concentrations. While early ASV measurements used macroscopic electrodes such as Hg drop electrodes to create surfaces appropriate for plating/stripping, more recent work on the method has used thin film metal electrodes manufactured in situ to replace these electrodes. Such electrodes are plated onto the surface of a primary electrode with the analyte species, resulting in a composite metal electrode from which the analyte(s) may be removed, identified, and measured. In this article, we'll look at how these unusual electrodes were created and how they're used in a range of applications. In both acidic and alkaline environments, a variety of metals (e.g., Hg, Bi, Sn, etc.) have showed promise as thin film ASV electrodes, and numerous metals, in addition to the analyte of interest, are typically deposited simultaneously to optimize plating/stripping behavior and improve sensitivity. It has been widely used to test dangerous metals in the environment, assess battery materials, and enable biological assays, among other uses, due to the comparatively simple nature of the measurement and its applicability for a wide range of pH. We'll go through these applications in further depth, as well as providing some insight into the thin film electrodes' future development and applications in ASV measurements.