About NR212 Proton / Cation Exchange Membrane (PEM)): Proton exchange membrane NR212, perfluorosulfonic acid ionic membrane NR212. 10*10cm for ion exchange in solution,for Flow Batteries and Electrochemical Applications Nafion Membrane is used to separate the anode and cathode compartment of Proton Exchange Membrane fuel cells and water electrolyzers. The thickness of this particular cation exchange membrane, Nafion 212 makes it suitable for many Hydrogen Air/Oxygen Fuel Cell applications. Nafion 212 is 50.8 micrometers thick. The membrane is positioned between a backing film and a coversheet. Chemours (DuPont) Nafion PFSA NR-212 membranes are based on chemically stabilized perfluorosulfonic acid/PTFE copolymer in the acid (H+) form, and exhibit substantially lower fluoride ion release compared to the non-stabilized polymer – a sign of improved chemical.