Catalysis of oxygen reduction in PEM fuel cell by seawater biofilm

The catalysis of oxygen reduction on metallic materials has been widely studied in the domain of aerobic corrosion. In this framework, it has been stated that seawater biofilms are able to catalyse efficiently oxygen reduction on stainless steels. This capacity was transferred here to the catalysis of the cathodic reaction of a proton exchange membrane fuel cell. A laboratory-scale fuel cell was designed with a stainless steel cathode, a platinum anode, and two separated liquid loops. The cathodic loop was air-saturated, while the anodic loop was hydrogen saturated. Seawater biofilm was previously grown on the stainless steel cathode, which was then set up into the fuel cell. The presence of the seawater biofilm on the stainless steel surface led to efficient catalysis of oxygen reduction. The biofilm-covered cathode was able to support current density up to 1.89 A/m2. Power density of 0.32 W/m2 was supplied with 1.34 A/m2 current density.