Catalyst layer network formation in polymer electrolyte membrane fuel cells

Various catalyst layer (CL) deposition techniques and membrane electrode assembly fabrication techniques were studied. To maximize performance, a new CL deposition technique was investigated: in situ sonication, where the morphology and fuel cell performance was compared to the standard hand painting technique. The in situ sonication method produced a more uniform, well dispersed, and less porous CL compared to the standard method. The fuel cell performance of this new technique was considerably lower than the standard CL fabrication technique. However, SEM images of the hand painted CL after fuel cell testing displayed different CL structures, a network of Nafion nanofibers connecting the catalyst particles. This newly discovered network microstructure and not the CL microstructure prior to fuel cell testing may be a primary cause for differences in fuel cell performance. The formation of Nafion nanofibers was studied and a new approach to fuel cell electrode optimization through a three-dimensional networked microstructure was presented. This is an abstract of a paper presented at the 2005 AIChE Annual Meeting and Fall Showcase (Cincinnati, OH 10/30/2005-11/4/2005).

Catalyst layer network formation in polymer electrolyte membrane fuel cells Conference Paper