Influence of Nafion Coatings and Surfactant on the Stripping Voltammetry of Heavy Metals at Bismuth-Film Modified Carbon Film Electrodes

Abstract

Nafion polymer coated bismuth-film-modified carbon film electrodes have been investigated for reducing the influence of contaminants such as surfactants in the anodic stripping voltammetry of trace metal ions. The influence of the coating on electrode response has been tested with both ex situ and in situ bismuth film deposition, with and without the polymer coating. The electrode assemblies and interfacial characteristics in the presence of the non-ionic surfactant Triton-X-100 have been probed with electrochemical impedance spectroscopy. The Nafion coating successfully decreases the adsorption of Triton on the bismuth film surface, and demonstrates that this strategy allows measurement of these trace metals in environmental samples containing surfactants.