Detection of OH Radicals Formed at PEFC Electrodes by Means of a Fluorescence Probe

A fluorescence probe method, which enables highly sensitive detection of OH radicals by forming a stable fluorescent product, was applied to a model reaction system of polymer electrolyte fuel cells (PEFCs). was successfully detected under open-circuit condition with a homemade test cell having reservoirs of a coumarin probe solution at both anode and cathode electrodes. The experiments with and in the probe solution suggested that the is produced via electrode reduction and oxidation of at the anode and cathode, respectively.