Detection of OH Radicals Generated in Polymer Electrolyte Membranes of Fuel Cells

Abstract

OH radicals formed during the PEFC operation of a single cell were detected by a fluorescence probe method with coumarin. The coumarin mols. impregnated in the polymer electrolyte membrane react with OH radicals to form a highly fluorescent product, umbelliferone. After PEFC operation under various conditions, the cross section of the membrane for five positions was monitored by a fluorescence microscope and the distribution of the OH radical d. in the membrane was evaluated. The difference among the radical densities at the five positions was large for each membrane. Probably the crossleak of O gas is a main process of the OH radical formation. on SciFinder(R)