Deactivation of Fe-N-C catalysts during catalyst ink preparation process

The membrane electrode assembly (MEA) is a core component of low-temperature fuel cells. first step MEA manufacturing the preparation catalyst ink suspension in which powder homogeneously dispersed liquid solvent through mechanical or sonic agitation. In this work, we have studied effects dispersion water alcohol solutions and subsequent drying processes on physicochemical properties Fe-N-C catalysts their electrocatalytic oxygen reduction activities. We find that dispersing model comprising only FeNxCy moieties treatment change neither its bulk structure nor surface composition, as indicated by various spectroscopic measurements before after treatment. However, zeta potential measurements, are very sensitive to chemistry functionalities present carbon surface, reveal becomes slightly more acidic, acido-basicity magnified with a) increasing temperature b) repetitions same wetting/drying This small results measurable reproducible decrease activity, shows positive correlation changes measured at pH = 1. Observed but not Pt/C, it surmised activities oxygen-reducing influenced carbonaceous support. Since wetting essential for fabrication cells, these suggest careful attention should be paid conditions employed prepare dry catalytic inks family order obtain highest possible ORR activity.