Applicability of microcapillary electrochemical droplet cell for monitoring microbiologically induced corrosion

Abstract

Formed biofilms can induce corrosion of metallic substrates through the secretion of corrosive chemical species, changes in local acidity, and the creation of galvanic oxygen concentration cells. Electrochemical testing is useful to study and monitor the growth of biofilms on metallic substrates. Macroelectrochemical testing gives an average measurement of all the chemical interactions and processes in the sampled area which is typically on the mm² to cm² scale. Microcapillary electrochemical droplet cell testing can perform AC and DC electrochemical measurements on the µm² scale, allowing measurements of local electrochemical processes in the picoampere range. Adapting this technique for use in studying microbiologically induced corrosion could provide high-resolution in-situ characterization of biofilm growth. Low alloy steel coupons were subjected to macro- and microelectrochemical techniques to characterize the influence of microbiological entities on the corrosion process.