Effect of PFSA Polymer Content in Catalyst Layer on PEFC Performance under Several Humidity Conditions

摘要

The effects on cell performance of Nafion~® content in 1 mg/cm~2 Pt with a Pt and carbon mixture containing 50 wt.% Pt (50 wt.%Pt/C-1 mgPt/cm~2) catalyst layers were studied under several humidified operating conditions at 80 ℃ and 1 atm. The optimum Nafion~® content for these conditions was 28-32 wt.% (0.76-0.95 mg/cm~2). 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.