Proton Conductive Inorganic-Organic Hybrid Membranes as an Electrolyte for Fuel Cells Prepared from 3-Glycidoxypropyltrimethoxysilane and Orthophosphoric Acid

Abstract

Proton conductive inorganic-organic hybrid membranes were prepared from 3-glycidoxypropyltrimethoxysilane, tetramethoxysilane and orthophosphoric acid by the sol-gel method. The ionic conductivity of the hybrid membranes increased with an increase in the content of orthophosphoric acid in the membranes, and was about 1 × 10⁻² S cm⁻¹ at 30°C under relative humidity of 80%, for the membranes with a molar ratio of P/Si = 1.5. Test cells were fabricated using the hybrid membranes with composite electrodes prepared from the precursor sol of the hybrid membranes and Pt black powders, and these cells were confirmed to work as a fuel cell.