초록 |
Layer by Layer self-assembly (LbL) method is a very useful way to make a polymeric thin film by using electrostatic attraction. And a polymer electrolyte membrane (PEM) for direct methanol fuel cell (DMFC) can be prepared by using the LbL method. Nafion® is most commonly used electrolyte in PEM fuel cells for its high proton conductivity and chemical stability, In spite of these merits, Nafion has high methanol permeability that reduces the overall cell efficiency. In order to reduce the methanol crossover, LbL film was made on the surface of modified Nafion membrane. Some of sulfonic acid group of Nafion is converted to alkyne group that can be crosslinked with another polymer which contains azide group by click reaction. LbL method was used for the preparation of fuel cell film by using the Nafion and azide modified cationic copolymer, and subsequent click reaction Obtained film was characterized by H-NMR, IR, IEC, water uptake, proton conductivity, and methanol permeability. Pristine Nafion film was used as a reference. |