| 초록 |
Perfluorosulfonic acid membranes with the trade name Nafion are most commonly used for electrolyte in polymer electrolyte membrane (PEM) fuel cells, because of their high proton conductivity and chemical stability. However, the Nafion is not satisfactory in many aspects especially due to its high methanol crossover when fueled with methanol. In order to overcome this drawback, crosslinked Nafion membranes were prepared, and examined its performances as PEM. The in-situ crosslinking of sulfonic acid was performed by addition of 1,1'-carbonyldiimidazole (CDI) and diamines as crosslinking agents. The reaction was monitored by ATR-FTIR and UV-vis spectroscopy, and the formation of sulfonamide linkages was confirmed. The performance of the membranes was measured in terms of IEC (ion exchange capacity), water uptake, proton conductivity, and methanol permeability. All data showed better performances and increased selectivities compared to those of Nafion117. |
