Abstract
The effects on cell performance of Nafion® content in 1 mg/cm2 Pt with a Pt and carbon mixture containing 50 wt.% Pt (50 wt.%Pt/C-1 mgPt/cm2) catalyst layers were studied under several humidified operating conditions at 80°C and 1 atm. The optimum Nafion® content for these conditions was 28-32 wt.% (0.76-0.95 mg/cm2). The value obtained using the 50 wt.%Pt/C catalyst was compared with reported values obtained using 20 wt.%Pt/C or 20 wt.%PtCr/C catalyst. The catalyst layer’s activation polarization with insufficient Nafion® decreases concomitantly with increased humidity, but that of a layer with excessive Nafion® increases with increased humidity.
