ИСТИНА

We propose to add oligomeric perfluorinated sulfonic acids directly into catalytic inks, when preparing active layers of electrodes for MEAs with PBI-based PA-doped membranes. It was known, that such compounds improve performance of PAFC upon addition them into the phosphoric acid electrolyte. It was also proposed to introduce them into ALs by means of impregnation. We detected better performance of assembled MEAs with PA-doped PBI-membrane, when F17-acid (F17C8SO3:K, potassium salt form) is introduced into the catalytic ink, which contains PTFE particles and HiSPEC 3000 (20% Pt @ C) catalyst dispersed in water–alcohol mixture. The F17-additive is a surfactant, and thus it improves stability of catalytic ink dispersion, promotes more controllable dispensing and uniform deposition of the active layer. During annealing at 350 C it melts together with PTFE and promotes better distribution of fluorinated material in the porous AL structure. In operating MEA it improves kinetic of the oxygen reaction.