Modification of a Nafion® ion exchange membrane by a plasma polymerization process

An ultra-thin anionic exchange layer was deposited on the surface of a Nafion® membrane. This layer was deposited from ethylene and ammonia using a glow–discharge plasma polymerization technique. The scanning electron microscopy (SEM), Fourier transform infrared attenuated total reflection (FTIR-ATR) spectra and X-ray photoelectron spectroscopy (XPS) showed that the resulting plasma film containing amine and amide was about 0.5 μm thick. The ion selectivity coefficient for H+ of the plasma modified Nafion® membrane was measured and the results showed that a linear Nernst response was exhibited and the selectivity of proton was enhanced. The resistance of modified Nafion® was only slightly higher than that of the Nafion® membrane.