De gradation rate va riance quantity fr m the an ode to the cathode in polymer electrolyte layer in PEM fuel cells

Basically, a poly mer electrolyte mem brane fuel cell converts hydrogen and oxygen electroc hemically into electric al power, h eat and water. A proto n exchang e membran e (PEM) serves as a solid electrolyte in a fuel cell, separating the anod e (hydrogen ) from the cathode (oxyge n/air) compartments. The most im portant property of io nomeric me mbranes e mployed in polymer electro lyte fuel cells, is the high protonic conductivity that they provid e under humidification con ditions and at current densities ty pically required in PE M fuel cells [۱, ۲]. The de gradation of perfluorinated sulfonic acid me mbrane (PF SA) in fuel cells is on e of the critical factors for fuel cells’ life time. It is clear from the literature st udies that chemical degrada tion of membrane is mainly due to the attack of radicals formed during the operation of a PE M fuel cell. Chemica l degradation of Nafion® involv es the attack of •OH radicals formed by the de compositio n of peroxide generated in the fuel cell. It was proposed that chemical attack occurs at the –COOH gr oups at the chain ends [۳].

کلیدواژه ها:

PEMFC ، Chemical degradation ، COOH ، •OH radicals