Oxygen Differential Cell

Definition

A corrosion mechanism in which low-oxygen areas become anodic while high-oxygen areas become cathodic, driving metal loss at the starved region.

Inside a biofilm, microbial respiration consumes oxygen at the metal interface while the outer film stays oxygen-rich, making the covered metal anodic. This is the same oxygen differential cell seen with passive deposits, but created and maintained by living organisms. The result is clean separation of anodic and cathodic regions and accelerated localized attack.

Related concepts

Mature community · Microbiologically influenced corrosion (MIC) · Under-Deposit Corrosion

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Part of The Blueprint of Water · ⚡ electrochemistry