Chitosan–PEO proton conducting polymer electrolyte membrane doped with NH₄NO₃

The polymer electrolyte membrane in this work was prepared using the solution casting technique. The polymer host is a blend of chitosan and polyethylene oxide. The solution of the blend was added with ammonium nitrate (NH4NO3) to supply the charge carriers for ionic conduction. From X-ray diffraction and scanning electron microscopy image, it can be inferred that the film of the 3∶2 chitosan–polyethylene oxide blend is the most amorphous and suitable to serve as polymer host. The sample containing 40 wt-%NH4NO3 exhibited the highest room temperature conductivity of 1·02×10−4 S cm−1. The salted samples were also characterised using X-ray diffraction and scanning electron microscopy in order to establish conductivity variation with different salt contents.