Journal of Membrane Science, Vol.185, No.1, 83-94, 2001
Protonic conducting organic/inorganic nanocomposites for polymer electrolyte membrane
Protonic conducting membrane can be used in many energy technological applications such as fuel cells, water electrolysis, hydrogen separation, sensors and other electrochemical devices. However, polymer electrolyte membrane usually lack thermal stability, resulting in narrow operational temperature windows. So, a new class of polymer membrane with high temperature stability and protonic conductivity is desired for many industrial applications. In this paper, new synthetic routes have been investigated for organic/inorganic nanocomposites hybrid polymer membranes of SiO2/polymer (polyethylene oxides (PEO); polypropylene oxide (PPO); polytetramethylene oxide (PTMO)). Novel protonic conducting properties have also been investigated. The materials have been synthesized through sol-gel processes in flexible, ductile free-standing thin membrane form. The hybrid membrane has been found to be thermally stable up to 250 degreesC and possess protonic conductivities of approximately 10(-4) S/cm at temperature windows from room temperature to 160 degreesC and relative humidity.
Keywords:organic/inorganic nanocomposites;silica/PEO hybrid;silica/PTMO hybrid;sol-gel process;protonic conducting membrane;solid polymer electrolytes;12-phosphotungstic acid (PWA)