A New Proton Conductive Membrane - Tungsten Peroxo Complex Doped Sol-Gel Organic/Inorganic ISfanocomposite Polymer

摘要

New family of proton conducting organic/inorganic hybrid polymer electrolyte membrane was prepared by sol-gel processes. The method involves the stabilization of metastable acidic tungsten oxide cluster in the polymer composite membrane. A free-standing, flexible and pale-yellowish transparent homogeneous membrane was formed from tungsten acidic homogeneous solution by sol-gel condensation with alkoxysilylated polyethylene oxide. The membrane showed very high protonic conductivity of 10"2~10"3 S cm'1 from R. T. to 120°C, especially, 1.4 x 10'2 S cnr at 80°C under 100% R. H. The structure of tungsten cluster moieties was neither peroxo complex nor WO3.2H2O, shown by infrared red and powder X-ray spectra. It is suggested that nano-size clusters are dispersed homogeneously in polymer matrix without long-range ordering. Tungsten complexes with carboxylate ligands such as malonic acid could form similar homogeneous membrane. Thermal and ionic transport properties could be controlled by these families of organic derivatives.