직접 메탄올 연료전지용 나피온 막의 폴리아닐린/Sulfonated Poly(ether sulfone) 다층 자기조립 박막에 의한 표면 개질
Surface Modification of Nafion by Layer-by-Layer Self-Assembled Films of Polyaniline and Sulfonated Poly(ether sulfone) for Direct Methanol Fuel Cell
1
조회
0
다운로드
0
인용
0
참고문헌
키워드
초록
본 연구에서는 나피온 막을 통한 메탄올 투과도를 감소시키기 위하여 양전하를 띠는 polyaniline (PANi)와 음전하를 갖는 sulfonated Poly(ether sulfone)(SPES)으로부터 다층 자기조립 박막법으 로 나피온 막의 표면을 개질하였다. PANi과 SPES는 열적 화학적으로 안정하며 매우 강직한 특 성을 띄고 있어, 나피온 막 표면에 다층 자기조립 박막 형성시 메탄올 투과도 감소 및 치수 안 정성의 향상을 기대할 수 있다. 자외선-가시광선 흡광분석에 의하여 PANi와 SPES의 다층박막의 형성이 균일하게 이루어짐을 확인 하였다. TEM 분석을 통하여 다층 자기조립 박막의 bilayer당 두께가 약 10 nm 정도임을 확인 하였다. 개질된 나피온 막은 순수한 나피온 막에 비하여 15% 의 이온전도도 감소가 일어났지만 67%의 높은 메탄올 투과도 감소를 나타내어 2.5배 높은 선택 도를 보였다. 5 M 메탄올을 연료로 사용한 연료전지 성능시험에서 개질된 나피온 막은 순수한 나피온 막에 비해 최대 전력 밀도가 30oC에서는 2.4배 증가, 60oC에서는 1.4배 향상을 나타내 었다
Abstract
In this study, Nafion membrane was modified to prevent methanol crossover by layer-by-layer self assembly using polyaniline (PANi) as a polycation and sulfonated poly(ether sulfone) (SPES) as a polyanion onto the Nafion surface. Since PANi and SPES possess thermal and chemical stability and rigid backbone, their layer-by-layer self-assembled films on the Nafion are expected to reduce methanol permeability and to increase mechanical stability. UV-Vis absorption spectroscopy verified a linear build-up of the multilayers of PANi and SPES. We found that the thickness per bilayer was about 10 nm by TEM measurement. Although modified Nafion membrane exhibited 15% decrease of proton conductivity, it reduceded 67% of methanol permeability compared to that of the pristine Nafion membrane, resulting in 2.5 times larger selectivity. At the performance test of the fuel cell using 5M methanol as a fuel, the modified Nafion membrane showed 2.4 times higher maximum power density at 30oC and 1.4 times larger at 60oC than the pristine Nafion
참고문헌 (19)
- M. Rikuawa, "'Proton-Conducting Polymer Electrolyte Membranes Based on Hydrocarbon Polymers'", Prog. Polym. Sci, 25, pp.1463~ (2007)
- J. A. Kerres, "'Development of Ionomer Membranes for Fuel Cell'", J. Membr. Sci, 185, pp.3~ (2001)
- S. R. Narayanan, "Handbook of Fuel Cells", John Wiley & Sons, 3, pp.894~ (2003)
- V. Tricoli, "'Proton and Methanol Transport in Poly (perfluoro-sulfonate) Membranes Containing Cs+ and H+ Cations'", J. Electrochem. Soc, 145, pp.3798~ (1998)
- C. Manea, "'Characterization of Polymer Blends of Polyethersulfone", Sulfonated Polysulfone and Polyethersulfone, J. Membr. Sci, pp.2003, 206[DOI]
- L. Li, "'Sulfonated Poly(ether ether ketone) Membranes for Direct Methanol Fuel Cell", J. Membr. Sci, 226, pp.159~ (2003)
- D. J. Jones, "'Recent advAnces in The Functionalization of Polybenzimidazole and Polyetherketone For Fuel Cell Applications'", J. Membr. Sci, 185, pp.41~ (2001)
- B. smitha, "'Synthesis and Characterization of Proton Conducting Polymer Membranes For Fuel Cells'", J. Membr. Sci, 225, pp.63~ (2003)
- K. M. Nouel, "'Nafion-based Composite Polymer Electrolyte Membranes'", Electrochim. Acta, 43, pp.2381~ (1998)
- F. Zhang, "'Novel Acidbase Polyimides Synthesized From Binaphthalene Dianhydride and Triphenylamine-containing Diamine As Proton Exchange Membranes'", J. Membr. Sci, 314, pp.24~ (2008)
- J. L. Casson, "'Reversal of Interfacial Dipole Orientation in Polyelectrolyte Superlattices Due to Polycationic Layers'", J. Phys. Chem, 104, pp.11996~ (2000)
- D. W. Kim, "'Ordered Multilayer Nanocomposites Prepared by Electrostatic Layer-by-Layer Assembly between Aluminosilicate Nanoplatelets and Substituted Ionic Polyacetylenes'", Chem. Mater, 14, pp.3925~ (2002)
- D. W. Kim, "'Hydrophobic Barrier: Molecular Selfassembly of Amphiphilic Polyacetylenes Within Aluminosilicate Nanoplatelets'", J. Membr. Sci, 275, pp.12~ (2006)
- D. W. Kim, "'Investigation on Methanol Permeability of Nafion Modified by Self-assembled Clay-nanocomposite Multilayers", Electrochimica Acta, 50, pp.659~ (2004)
- J. H. Cheung, "'Molecular-Level Processing of Conjugated Polymer. 3. Layer-by-Layer Manipulation of Polyaniline via Electrostatic Interaction", Macromolecules, 30, pp.2712~ (1997)
- W. B. Stockton, "'Molecular-Level Processing of Conjugated Polymer. 4. Layer-by-Layer Manipulation of Polyaniline via Hydrogen-Bonding Interaction'", Macromolecules, 30, pp.2717~ (1997)
- F. Xie, "'Effect of the Anodic Diffusion Layer on the Performance of Liquid Fuel Cells'", Fuel Cells, 7, pp.319~ (2007)
- M. S. Wilson, "'Thin-film Catalyst Layers for Polymer Electrolyte Fuel Cell Electrodes'", J. Appl. Electrochem, 22, pp.1~ (1992)
- Q. Ye, T, "'A Natural-circulation Fuel Delivery System for Direct Methanol Fuel Cells'", J. Power Sources, 147, pp.196~ (2005)