Abstract
Nafion membranes with a monolayer of pores on one surface (P-Nafion) were prepared by casting a Nafion SE20092 dispersion containing ortho-dichlorobenzene. The pores are not connected but provide 2μm large openings, increasing the membrane surface by one dimension. The thickness of the porous layer is typically <5μm. In catalyst coated membranes the catalyst layer penetrated the pores well. The effect on the performance of a polymer electrolyte fuel cell (PEFC) was investigated at 95°C. The porous layer formed the cathode, to enhance water back diffusion. After 24h equilibration, 30-35μm thick P-Nafion gave 10-16% higher current density, reaching 858mA/cm2 at 0.4V and 50% rh. N211 and P-Nafion equilibrated for 8min showed peak power densities of 56 and 208mW/cm2 under anhydrous conditions, respectively, indicating that drying processes are slowed down. The stability of a MEA was tested for 240h at 0.4V and 50% rh (anode/cathode), without observable degradation. Under fully humidified conditions, the electrochemical surface area (ECSA) increased 40% in comparison to a N211 based MEA. At 65°C, the ECSA more than doubled, showing 141m2/g Pt. Also influence of the pores on water transport through a membrane and stability against membrane-electrode delamination were considered.
| Original language | English |
|---|---|
| Pages (from-to) | 199-205 |
| Number of pages | 7 |
| Journal | Journal of Membrane Science |
| Volume | 460 |
| DOIs | |
| Publication status | Published - 2014 Jun 15 |
| Externally published | Yes |
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Keywords
- Fuel cells
- Hierarchical structures
- Nafion membranes
- Porous surfaces
- Water management
ASJC Scopus subject areas
- Physical and Theoretical Chemistry
- Materials Science(all)
- Biochemistry
- Filtration and Separation
Cite this
Nafion membranes with a porous surface. / Dang, Quoc Khanh; Henkensmeier, Dirk; Krishnan, N. Nambi; Jang, Jong Hyun; Kim, Hyoung Juhn; Nam, SukWoo; Lim, Tae Hoon.
In: Journal of Membrane Science, Vol. 460, 15.06.2014, p. 199-205.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Nafion membranes with a porous surface
AU - Dang, Quoc Khanh
AU - Henkensmeier, Dirk
AU - Krishnan, N. Nambi
AU - Jang, Jong Hyun
AU - Kim, Hyoung Juhn
AU - Nam, SukWoo
AU - Lim, Tae Hoon
PY - 2014/6/15
Y1 - 2014/6/15
N2 - Nafion membranes with a monolayer of pores on one surface (P-Nafion) were prepared by casting a Nafion SE20092 dispersion containing ortho-dichlorobenzene. The pores are not connected but provide 2μm large openings, increasing the membrane surface by one dimension. The thickness of the porous layer is typically <5μm. In catalyst coated membranes the catalyst layer penetrated the pores well. The effect on the performance of a polymer electrolyte fuel cell (PEFC) was investigated at 95°C. The porous layer formed the cathode, to enhance water back diffusion. After 24h equilibration, 30-35μm thick P-Nafion gave 10-16% higher current density, reaching 858mA/cm2 at 0.4V and 50% rh. N211 and P-Nafion equilibrated for 8min showed peak power densities of 56 and 208mW/cm2 under anhydrous conditions, respectively, indicating that drying processes are slowed down. The stability of a MEA was tested for 240h at 0.4V and 50% rh (anode/cathode), without observable degradation. Under fully humidified conditions, the electrochemical surface area (ECSA) increased 40% in comparison to a N211 based MEA. At 65°C, the ECSA more than doubled, showing 141m2/g Pt. Also influence of the pores on water transport through a membrane and stability against membrane-electrode delamination were considered.
AB - Nafion membranes with a monolayer of pores on one surface (P-Nafion) were prepared by casting a Nafion SE20092 dispersion containing ortho-dichlorobenzene. The pores are not connected but provide 2μm large openings, increasing the membrane surface by one dimension. The thickness of the porous layer is typically <5μm. In catalyst coated membranes the catalyst layer penetrated the pores well. The effect on the performance of a polymer electrolyte fuel cell (PEFC) was investigated at 95°C. The porous layer formed the cathode, to enhance water back diffusion. After 24h equilibration, 30-35μm thick P-Nafion gave 10-16% higher current density, reaching 858mA/cm2 at 0.4V and 50% rh. N211 and P-Nafion equilibrated for 8min showed peak power densities of 56 and 208mW/cm2 under anhydrous conditions, respectively, indicating that drying processes are slowed down. The stability of a MEA was tested for 240h at 0.4V and 50% rh (anode/cathode), without observable degradation. Under fully humidified conditions, the electrochemical surface area (ECSA) increased 40% in comparison to a N211 based MEA. At 65°C, the ECSA more than doubled, showing 141m2/g Pt. Also influence of the pores on water transport through a membrane and stability against membrane-electrode delamination were considered.
KW - Fuel cells
KW - Hierarchical structures
KW - Nafion membranes
KW - Porous surfaces
KW - Water management
UR - http://www.scopus.com/inward/record.url?scp=84896529465&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84896529465&partnerID=8YFLogxK
U2 - 10.1016/j.memsci.2014.03.003
DO - 10.1016/j.memsci.2014.03.003
M3 - Article
VL - 460
SP - 199
EP - 205
JO - Jornal of Membrane Science
JF - Jornal of Membrane Science
SN - 0376-7388
ER -