Novel inorganic/organic hybrid membranes for proton exchange

Two types of inorganic/organic hybrids comprising Brønsted acid-base ionic groups have been prepared and studied for proton exchange membranes (PEM) applications. The hybrid membranes have a highly cross-linked silicon-oxygen backbone and trifluoromethanesulfonimide (HTFSI) doped organic amine groups. The Si-O backbone provides the membranes thermal/chemical/mechanical properties and the HTFSI-doped amine end groups provide the proton conducting properties. The membranes exhibited proton conductivities of 10 S/cm at elevated temperature (≥ 130 °C) and anhydrous conditions. Under fully hydrated conditions, the membranes showed high proton conductivity (10 S/cm) and low methanol/water crossover rate.