Protonic conducting properties of sol-gel derived organic/inorganic nanocomposite membranes doped with acidic functional molecules

High temperature protonic conducting polymer membranes provide new technolo gical applications in electrochemical devices including electrochromic disp lays, chemical sensors, fuel cells and others. Organic/inorganic nanocompos ite membranes consisting of SiO2/PEO (polyethylene oxides) hybrids are a re markable family of isotropic, flexible, amorphous polymer materials, which have been synthesized through sol-gel processes. The hybrid membrane doped with acidic moieties such as monododecylphosphate or phosphotungstic acid s hows good protonic conductivities at high temperatures above 100 degrees C. The protonic conducting membrane was found to be thermally stable at high temperatures because of the inorganic SiO2 framework in the nanocomposite m atrix. (C) 1999 Elsevier Science B.V. All rights reserved.