| 초록 |
Direct methanol fuel cell (DMFC) is one of the promising candidates for portable electrical source. However, methanol crossover is a significant problem that hinders the commercialization of DMFC. High methanol crossover caused loss of fuel, reduced fuel efficiency, mixed potential at the cathode and poisoned catalyst. In this study, in order to block the methanol crossover through Nafion, methanol blocking layer formation on the surface of Nafion by layer-by-layer self-assembly with permselective layered silicate (AMH-3) and polyelectrolyte. AMH-3 can be used as methanol blocking layer for DMFCs because of its pore size has smaller than diameter of methanol, and bigger than that of water, its three-dimensional micro-porous structure, and its high aspect ratio. Herein, AMH-3 was synthesized by the hydrothermal reaction, and then AMH-3 was modified via the acid treatment. AMH-3 and acid-treated AMH-3 were characterized by XRD, FE-SEM, 29Si MAS NMR, and FT-IR. AMH-3/polyelectrolyte methanol blocking layer were prepared onto Nafion by layer-by-layer self-assembly (LBL) with various LBL cycle numbers, and then measured its methanol permeability and proton conductivity. The methanol permeability and proton conductivity decreased with increasing number of LBL cycle. |
