Influence of sulfonated SBA-15 on fuel cell performance of sulfonated polysulfone electrolyte membranes

The prepared mesoporous SBA-15 (Santa Barbara Amorphous-15) was sulfonated and used as filler for the preparation of sulfonated polysulfone based composite electrolyte membranes. The SBA-15 and polysulfone were sulfonated using 3-mercaptopropyl trimethoxysilane and trimethylsilyl chlorosulfonate, respectively. The different weight percentages (1, 3, and 5 wt%) of sulfonated SBA-15 (SSBA-15) were used to prepare composite electrolyte membranes. Water uptake, ion exchange capacity, swelling ratio and proton conductivity of the composite membranes were studied for assessing the suitability of the electrolyte membranes for use in fuel cells. Characterization techniques such as FT-IR, XRD, SEM, TEM and Brunauer-Emmett- Teller were used to study the physico-chemical properties of the electrolyte membranes. TEM and BET analysis showed that SBA-15 retained its mesoporous structure even after sulfonation process. The prepared membranes were then tested in an in-house built single-cell fuel cell using hydrogen as fuel and oxygen as the oxidant. The fuel cell study showed that the presence of Sulfonated SBA-15 in the polymer matrix provided additional ion exchange sites and retained water for proton transfer which resulted in higher power density of 815 mW/cm(2) with SPSU + 3% SSBA-15 membrane as compared with Nafion 117((R)).

Automated summary

Sulfonated mesoporous SBA-15 was used as a filler for the preparation of sulfonated polysulfone based composite electrolyte membranes. The physical and chemical properties of the membranes were analyzed using various characterization techniques. The results showed that sulfonated SBA-15 provided additional ion exchange sites and retained water, leading to increased power density in the fuel cell.