Custom-made SPEEK polymer composite membranes using perovskite structured SrCeO3 for DMFC applications

The polymer composite membranes based on sulfonated poly (ether ether ketone) (SPEEK) and strontium cerate (SrCeO3) were prepared by dispersing SrCeO3 nanoparticles into SPEEK solution with the solvent casting method. The prepared composite membranes are characterized by X-ray diffraction analysis, Fourier infrared spectroscopy, scanning electron microscopy, water uptake, ion exchange capacity, proton conductivity, methanol permeability, thermogravimetric analysis, and oxidative stability. Significant improvement has been attained through the successful combination of the organic and inorganic phases. TGA showed that all the composite membranes exhibited good thermal stability. The maximum proton conductivity of 32.1 mS/cm was achieved at (25 °C) upon incorporating 06 wt.% of the SrCeO₃ nanoparticle. The excellent proton conductivity of the membranes can be attributed to the presence of SrCeO₃ nanoparticles, which can act as pathways for proton transport. The prepared polymer composite membranes exhibited high selectivity compared with pure SPEEK and Nafion 117. From the observed results, the prepared 94 wt% SPEEK and 06 wt% SrCeO₃ composite membranes can be considered opposite polymer electrolyte membranes for the application of direct methanol fuel cell (DMFC) applications.