Degradation of proton exchange membrane by Pt dissolved/deposited in fuel cells

摘要

An accelerated single cell test and single electrode cell test were carried out to investigate membrane degradation by Pt dissolved/deposited on the membrane. For a cell operating under accelerated conditions (OCV, 90℃, anode RH 0%, cathode O_2 supply), MEA analyses revealed that Pt particles were deposited in the membrane at the anode side, with a decrease in F, O, and C content near the anode side of the membrane. Dissolved Pt from the cathode showed that Pt existed mainly in the form of Pt~(2+) ionic species. Oxygen and hydrogen helped Pt dissolution from the cathode and Pt deposition in the membrane, respectively. Radical formation on deposited Pt in the membrane was detected by electron spin resonance (ESR). Fluoride emission rate (FER, an indicator of membrane degradation rate) increased with an increase in the amount of Pt in the membrane.