Hydroscopic strontium hydroxide/Nafion composite membrane for a direct methanol fuel cell

A commercial Nafion membrane was modified by impregnating hydroscopic strontium hydroxide to retain electrochemically produced water in the membrane. Hydroscopic strontium hydroxide/Nafion (Sr/Nafion) composite membranes were produced by an in situ acid-catalyzed sol-gel reaction in Nafion perfluorosulfonic acid films. The amounts of hydroscopic strontium hydroxide in the composite membranes varied depending on the concentration of Sr-isopropoxide (SrIPP). The physical and chemical properties of the composite membranes were investigated by FT-IR and SEM-EDS. The water uptake contents and thermal properties of the composite membrane were analyzed by TGA. The cell resistance of the composite membranes was measured using an impedance analyzer. The performance of the membrane electrode assembly (MEA) using a composite membrane was evaluated in single cell tests at 30 and 60 °C.