New Proton-Exchange Membrane (PEM) Based on the Modification of Sulfonated Polystyrene with MIL-53(Al)-NH2 for Direct-Methanol Fuel Cell

In this study, modified sulfonated polystyrene (SPS) was used as a base for membrane fabrication in Direct Methanol Fuel Cells (DMFCs). The sulfonated polystyrene (SPS) was prepared using ethylsulfate and polystyrene with sulfate attached to the para-position of some phenyl groups in polystyrene backbone and conducted by polyethylene (PE) and different amounts of MIL-53(Al)-NH2 as metal-organic material, to obtain SPS-PE-MIL-53 as a novel proton-exchange membrane. The membranes were characterized using FT-IR spectroscopy, SEM, and TGA analysis. The proton conductivity, water uptake, oxidative resistance, ionic conductivity, and methanol permeability of the membranes were examined to assess their performance in a direct methanol fuel cell. The modified membrane containing 1% wt SPS, 1% wt PE, and 0.25% wt MIL-53 showed relatively better performance than the other prepared membranes with the selectivity factor of 7.17 × 104 S.s/cm3 and a maximum peak power density of 17.04 mW/cm2 with a maximum current density of 115.38 mA/cm2.