Amino-Functionalized Mesoporous Silica Based Polyethersuflone-Polyvinylpyrrolidone Composite Membrane for Elevated Temperature Fuel Cells

Inorganic-organic nanostructured hybrid membranes of polyethersuflone (PES)-polyvinylpyrrolidone (PVP) were prepared with mesoporous silica materials. Hollow mesoporous silica is synthesized via cationic surface-assistant etching method, while amino-functionalized hollow mesoporous silica and amino-functionalized mesoporous silica spheres were synthesized via post-grafting strategy. After the addition of mesoporous silica and amino-functionalized mesoporous silica into the matrix of PA doped PES-PVP composite membranes, all composite membranes show similar PA uptake. However, the proton conductivity of the composite membranes increases significantly with the substantial decrease in the activation energy for proton diffusion, especially for the amino-functionalized hollow mesoporous silica material. That reason is most likely due to the facilitated proton transportation in the ordered mesoporous channels via the hydrogen bond between the –NH2 groups and H3PO4. Cell performance also confirms the superiority of the addition of inorganic fillers in PES-PVP membrane, and the highest peak power density at 180 oC was 480 mW cm-2 for NH2-HMS based composite membrane, which is 92.7 % higher than that of PA doped PES-PVP composite membrane at the identical condition. The results show promising application of NH2-HMS based PES-PVP composite membrane for elevated temperature proton exchange membrane fuel cells. Figure 1