Nafion/benzotriazole functionalized montmorillonite nanocomposites: novel high-performance proton exchange membranes

Here we describe preparation and characterization of novel ion exchange polymer nanocomposites for fuel cells applications. Montmorillonite (MMT) nanoclay is modified using amino benzotriazole (BTA) via ion exchange reaction. X-ray diffraction patterns confirmed modification of MMT. This BTA-MMT was then used to produce Nafion based nanocomposite membranes with exfoliated microstructures at different loading weights. Transport property (proton conductivity and methanol permeability) results revealed that incorporation of BTA-modified MMT into Nafion (R) results in significantly reduced methanol crossover while maintaining proton conductivity. Direct methanol single fuel cell tests confirmed a cell efficiency of 21% for Nafion/BTA-MMT-3 wt% compared to 13.72% for conventional Nafion117 membrane at 5 M methanol feed, and also a higher power density of 144 mW cm(-2) in comparison with 39 mW cm(-2) for Nafion 117. Owing to these features, prepared Nafion/BTA-MMT membranes can be considered as promising polymeric electrolytes for fuel cell applications.