Influence of impurities in TiO₂ coatings on electrode potential of photocatalytic anode assembling to marine microbial fuel cell

The electrochemical measurement and surface morphology analysis of TiO ₂ coatings were conducted to improve the performance of microbial fuel cell (MFC) in natural seawater. From the experimental results, the 95.2% TiO₂ purity electrode caused the noble shift of electrode potential which resulted from suppression of the photocatalytic effect. This phenomenon did not occur in 99.9% purity coatings, so the influence of impurities such as Si or Zr contained in the coatings was considered. Furthermore, the localized potential at the segregation of Si or Zr was higher than that of the rest, so the electrode potential of TiO₂ coated anode was considered to be affected by the localized corrosion which had occurred beneath the deteriorated TiO₂ coatings.