A quaternized mesoporous silica/polysulfone composite membrane for an efficient alkaline fuel cell application

Abstract

Mesoporous silica (SBA-15) was synthesized and quaternized via chloromethylation followed by amination. Quaternized SBA-15 (QSBA) was characterized by FTIR, solid state ¹³C NMR, BET, XRD and TEM. The QSBA was then incorporated into quaternary polysulfone (QPSu) in different weight percentages (1–4%) to form high ion exchange capacity composite membranes. The composite membranes were analysed by SEM and XRD. The water uptake, ion exchange capacity and hydroxyl conductivity of the composite membrane were studied for the suitability of the membrane in alkaline fuel cells. A membrane electrode assembly was constructed using a carbon supported platinum (Vulcan XC-72) anode, cathode catalysts and a QPSU/3% QSBA-15 composite membrane and tested in an AFC. A maximum power density of 298 mW cm⁻² was achieved at 60 °C. The experimental results showed that the QPSU/QSBA-15 composite membrane exhibited a promising electrochemical performance in an AFC.