Enhancing Water Retention, Transport, and Conductivity Performance in Fuel Cell Applications: Nafion-Based Nanocomposite Membranes with Organomodified Graphene Oxide Nanoplatelets

The synergistic combination of Nafion and sulfonated graphene oxide (GOsulf) in nanocomposite membranes emerged as a promising strategy for advancing proton exchange membrane fuel cell (PEMFC) technology. In the pursuit of elucidating the effect of GOsulf introduction on transport properties and electrochemical performance of Nafion, this work provides a systematic study combining swelling tests, water release tests, 1H NMR characterization, and Electrochemical Impedance Spectroscopy (EIS) investigation. The incorporation of organomodified GO nanolayers alters the distribution of water molecules within the hydrophilic domains of Nafion and produces a considerable increase in the “bound-water” fraction. This increases its water retention capability while ensuring very high diffusivity even under high temperatures, i.e., 1.5 × 10−5 cm2 s−1 at 130 °C. These peculiar features enable Naf-GOsulf to successfully operate under a dehydrating environment, yielding a proton conductivity of 44.9 mS cm−1 at 30% RH.