Reducing biofouling on optical oxygen sensors; a simple modification enabling sensor cleaning via water splitting.

Biofouling is a major challenge in environmental sensing. Current mitigation strategies are often expensive, energy consuming or require toxic chemicals. In this contribution electrochemical biofouling control is evaluated as an alternative approach to reduce biofouling on an optical O 2 sensor (optode). By using the outer stainless-steel sleeve of the optode as an electrode, water splitting increases the local pH and forms H 2 bubbles close to the optode surface. As seen in a biofouling assay, the combination of those processes leads to biofilm removal when compared to a non-modified optode. The findings suggest that electrochemical biofouling control can be an attractive, low-cost alternative to current biofouling mitigation strategies and that this approach may not be limited to O 2 optodes.