Characterization of sPEEK/Chitosan Membrane for the Direct Methanol Fuel Cell

The proton exchange membrane is a key component of Direct Methanol Fuel Cell (DMFC) as proton conductor and also fuel separator. Some novel polymeric electrolyte membranes for DMFC with have been developed to lower methanol permeability but are able to work at sufficient conductivity. The composite of the natural polymer chitosan and sulfonated polyether ether ketone was prepared. This composite membrane was characterized using Fourier-transfonn infrared spectrometry, X-ray diffraction, water uptake and swelling degree, ion exchange capacity and methanol permeability. The FTIR measurement exposed interaction between the sulfonic acid group of sPEEK and amino group of chitosan. The methanol diffusion coefficient of the composite membrane was lower than that of the pure sPEEK and Nafion (R) 117 membranes. The result indicated that the layered chitosan on sPEEK showed improved performance of sPEEK or chitosan membranes.