Polybenzimidazole-based membranes as a real alternative to Nafion for fuel cells operating at low temperature

Composite proton-conducting membranes, based on polybenzimidazole (PBI) and imidazole-derivatized silica are presented. The addition of even small amounts (similar to 10 wt %) of filler causes an improvement in the permanent proton conductivity by < 10(3). The preparation of PBI composite membranes with basic functionalities is a promising way to make possible their use in PEMFCs operating around 120 degrees C, the temperature required for automotive applications.