Interfacial Effects Between the Structured Nanofillers and Nafion Matrices on the Performance of H2-PEM Fuel Cell

Abstract

This PhD thesis consists of the studies on four types of Nafion-based composite membranes in pursuit of high proton flux in a low moisture-content matrix because this is a bottleneck the current proton exchange membrane fuel cell technology faces. The composite matrixes were fabricated through: 1st, doping Nafion by p-aramid nano flakes, which gave rise to a proton transport less dependent on matrix moisture; 2nd, doping Nafion by a substituted poly(p-phenylene) oligomer to utilize conjugated aromatic segments as fast proton-hopping platforms; 3rd, incorporating highly porous carbon nanospheres (PCNs) into Nafion, leading to a dual effect: formation of a semi-interpenetrating network and moisture retention. Both impact proton transport in relatively dry Nafion matrix; and 4th, implanting hollow polymeric spheres (HPSs) in Nafion. These spheres served as fast proton transport spots. The filler-matrix interactions were examined through not only single fuel cell assessment but also colloidal, rheological, mechanical and thermal characterizations.