Document Type


Subject Area(s)

Chemical Engineering


Membrane electrode assemblies ~MEAs! made from polyetheretherketone ~PEEK! showed excellent fuel cell performance and thermal stability in the presence of substantial CO at elevated temperatures ~i.e., 120°C! in proton exchange membrane fuel cells ~PEMFCs!. For example, the current from a MEA made from PEEK membrane at 0.6 V and 120°C was 0.50 A/cm2 when run on pure hydrogen and 0.45 A/cm2 when run on reformate ~50% H2 , 1300 ppm CO, and balance N2). The current density from a MEA made from Nafion at 0.6 V and 120°C was 0.61 A/cm2 when run on pure hydrogen. The main difference between these two MEAs is that the ionic conductivity of the PEEK membrane at 120°C was 3.38 3 1022 S/cm, which is approximately three times lower than Nafion. Although it is not surprising that CO tolerance increases with increasing temperature, we are the first to show less than 10% drop in performance with 1300 ppm CO at 120°C. Even though Nafion membranes have higher conductivity, PEEK membranes lasted for 350 h thereby outlasting Nafion membranes by seven to eight times.