| 초록 |
Composite ionomer membranes were prepared and their properties were investigated. 5 wt% Nafion (Dupont, EW=1,100) solution dissolved in N,N-dimethylacetamide and 2-propanol was blended with PVdF-HFP (Elfatochem, Kynar 2801) solution dissolved in same solvents, and then Nafion/PVdF(N/P) blend membranes were obtained by solvent casting. The composite membranes were prepared via impregnation of blend membrane with zirconyl chloride and 1 M phosphoric acid using specially designed cell. Zirconium phosphate particles in blend membrane were measured by X-ray diffraction and observed by FE-SEM. 20 wt% zirconium phosphate impregnated blend membrane were confirmed by thermal gravitational analysis. Carbon-supported Platinum catalysts (Pt/C 40 wt% Pt) were directly sprayed on composite membrane for fabrication of MEA. Unit cell (25 cm2) performance was tested using high purity H2/O2. Nafion 117 and N/P (6/4) membrane reached only 250 mA/cm2 and 150 mA/cm2 at 0.5 V at a temperature 130 ℃, respectively, but composite membrane (N/P/Zr = 6/4 20) reached about 400 mA/cm2 at the same condition.
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