| 초록 |
Among various fuel cells, direct methanol fuel cells (DMFCs) are suited for portable devices or transportation applications owing to their high energy density at low operating temperatures. Yet they have major drawbacks such as methanol crossover causing the decrease of selectivity (proton conductivity/methanol permeability). In this study, in order to increase the selectivity of the membranes for DMFCs, one approach is attempted; Nafion/sulfated β-cyclodextrin (sb-CD) composite membranes providing tortuous pathway of methanol and increasing reactive sites. Nafion/sb-CD composite membranes with sb-CD contents of 1, 3, 5 wt% were prepared by the solution casting method. The water uptake, IEC, selectivity, ionic cluster pore size, and maximum power density of composite membranes were found to increase with increases in the sb-CD content. All things considered, 5 wt% loading was an optimized content of sb-CD in the Nafion matrix to exhibit the best overall performance in DMFCs. |
