Polymer coatings as separator layers for microbial fuel cell cathodes

▶ Spray coatings on the cathode (water facing side) were examined for microbial fuel cells to improve performance. Materials included anion exchange, cation exchange, and neutral polymers. ▶ The anion exchange polymer coating resulted in more power than the cation exchange coating and the power produced with the anion exchange polymer coating was only slightly less than an uncoated cathode that displayed much lower coulombic efficiency than the coated cathodes.. ▶ Our results demonstrated that there is a trade off between power and coulombic efficiency, and that cathodes with a thin anion exchange polymer coating showed the most promise for controlling oxygen transfer while minimally affecting power production.