초록 |
Organic/inorganic hybrid membranes based on Nafion and polyhedral oligomeric silsesquioxane bearing two sulfonic acid groups(sPOSS) were prepared as candidate materials for direct methanol fuel cell (DMFC) applications. Microstructure of the hybrids were characterized by means of WAXD, EDX-SEM, and AFM. Performance of the hybrid as proton exchange membrane was evaluated in terms of methanol permeability, proton conductivity and single cell performance. Results showed that the POSS molecules were aggregated to form a nanocrystal in Nafion matrix. The proton conductivity of hybrid membrane showed 0.08S/cm at 30wt% of sPOSS, which is comparable to that of Nafion and methanol permeability for the hybrid membrane is about 80% lower than for Nafion. It was postulated that the hydrophobic POSS nanocrystals provide a barrier to methanol permeation across the membrane. |