Fabrication of new fullerene composite membranes and their application in proton exchange membrane fuel cells

New fullerene derivatives, tri-cyanohydrofullerene, HC60(CN)3, and poly{4-[2-[2-(2-methoxyethoxy)ethoxy]ethoxy]benzyl}fullerene, C60(TEO)n, have been synthesized as additives for proton conducting membranes. The new compounds have been incorporated in Nafion® to fabricate a composite by a newly developed solution cast method. The fullerene–Nafion® membranes exhibited an excellent handling with no extensive phase separation. C60(TEO)n has also been found to be very effective in improving the dispersion of HC60(CN)3 in the Nafion® matrix. The fullerene composite membranes have demonstrated enhanced proton conductivity under low relative humidity conditions compared to a recast Nafion® membrane. The membrane characterization was performed through optical microscopy, SEM, and water uptake measurements.