STRUCTURAL AND PROOTN CONDUCTIVITY STUDIES ON PHOSPHOSILICATE/HETEROPOLYACID BASED COMPOSITE MEMBRANES

摘要

Inorganic-organic composite membranes have been fabricated by a sol-gel method using phosphosilicate (SiO_2/P_2O_5), silicotungstic acid (SiWA) and precursors and their properties were characterized. Analysis of the proton conductivity was performed under various temperatures with relative humidity. The composites showed high proton conductivity values in the range of 10~(-2)-10~(-1) S/cm, and such values were due to a proton-conducting path through the 3-mercaptopropyltrimethoxysilane (MPTMS), 3-aminopropyltriethoxysilane (APTES) and 3-glycidyloxypropyltrimethoxysilane (GPTMS)-derived pseudo-polyethylene oxide network in which sulfonic acid acted as a proton donor. These results classified the membranes as very promising novel materials for fuel cell applications.