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The oxygen reduction reaction (ORR) in the cathode catalyst layer (CCL) of polymer electrolyte fuel cells (PEFC) is one of the major causes of performance loss during operation. In addition, the CCL is the most expensive component due to the use of a Pt catalyst. Apart from the ORR itself, the species transport to and from the reactive sites determines the performance of the PEFC. The effective transport properties of the species in the CCL depend on its nanostructure. Therefore a three-dimensional reconstruction of the CCL is required. A series of two-dimensional images was obtained from focused ion beam - scanning electron microscope (FIB-SEM) imaging and a segmentation method for the two-dimensional images has been developed. The pore size distribution (PSD) was calculated for the three-dimensional geometry. The influence of the alignment and the anisotropic pixel size on the PSD has been investigated. Pores were found in the range between 5 nm and 205 nm. Evaluation of the Knudsen number showed that gas transport in the CCL is governed by the transition flow regime. The liquid water transport can be described within continuum hydrodynamics by including suitable slip flow boundary conditions.
Yang, H.; Zhao, T. S.; Ye, Q. Pressure drop behavior in the anode flow field of liquid feed direct methanol fuel cells. J. Power Sources 2005, 142, 117–124.
Manke, I.; Hartnig, C.; Gruenerbel, M.; Lehnert, W.; Kardjilov, N.; Haibel, A.; Hilger, A.; Banhart, J.; Riesemeier, H. Investigation of water evolution and transport in fuel cells with high resolution synchrotron X-ray radiography. Appl. Phys. Lett. 2007, 90, 174105.
Schroeder, A.; Wippermann, K.; Mergel, J.; Lehnert, W.; Stolten, D.; Sanders, T.; Baumhöfer, T.; Sauer, D. U.; Manke, I.; Kardjilov, N. Combined local current distribution measurements and high resolution neutron radiography of operating direct methanol fuel cells. Electrochem. Commun. 2009, 11, 1606–1609.
Sinha, P. K.; Halleck, P.; Wang, C. Y. Quantification of liquid water saturation in a PEM fuel cell diffusion medium using X-ray microtomography. Electrochem. Solid-state Lett. 2006, 9, A344–A348.
Ziegler, C.; Gerteisen, D. Validity of two-phase polymer electrolyte membrane fuel cell models with respect to the gas diffusion layer. J. Power Sources 2009, 188, 184–191.
Xie, Z.; Navessin, T.; Shi, K.; Chow, R.; Wang, Q.; Song, D.; Andreaus, B.; Eikerling, M.; Liu, Z.; Holdcroft, S. Functionally graded cathode catalyst layers for polymer electrolyte fuel cells. J. Electrochem. Soc. 2005, 152, A1171–A1179.
Gerteisen, D.; Heilmann, T.; Ziegler, C. Modeling the phenomena of dehydration and flooding of a polymer electrolyte membrane fuel cell. J. Power Sources 2009, 187, 165–181.
Eikerling, M. Water management in cathode catalyst layers of PEM fuel cells. J. Electrochem. Soc. 2006, 153, E58–E70.
Torquato, S.; Haslach, H. W. Jr. Random Heterogeneous Materials: Microstructure and Macroscopic Properties; Springer: New York, 2002.
Mukherjee, P. P.; Wang, C. Y. Direct numerical simulation modeling of bilayer cathode catalyst layers in polymer electrolyte fuel cells. J. Electrochem. Soc. 2007, 154, B1121–B1131.
Levitz, P. Off-lattice reconstruction of porous media: Critical evaluation, geometrical confinement and molecular transport. Adv. Colloid. Interf. Sci. 1998, 76, 71–106.
Torquato, S. Statistical description of microstructures. Annu. Rev. Mater. Res. 2002, 32, 77–111.
Kim, S. H.; Pitsch, H. Reconstruction and effective transport properties of the catalyst layer in PEM fuel cells. J. Electrochem. Soc. 2009, 156, B673–B681.
Siddique, N. A.; Liu, F. Process based reconstruction and simulation of a three-dimensional fuel cell catalyst layer. Electrochim. Acta 2010, 55, 5357–5366.
Möbus, G.; Inkson, B. J. Nanoscale tomography in materials science. Mater. Today 2007, 10, 18–25.
Holzer, L.; Indutnyi, F.; Gasser, P. H.; Munch, B.; Wegmann, M. Three-dimensional analysis of porous BaTiO3 ceramics using FIB nanotomography. J. Microscopy 2004, 216, 84–95.
Wilson, J. R.; Kobsiriphat, W.; Mendoza, R.; Chen, H. Y.; Hiller, J. M.; Miller, D. J.; Thornton, K.; Voorhees, P. W.; Adler, S. B.; Barnett, S. A. Three-dimensional reconstruction of a solid-oxide fuel-cell anode. Nat. Mater. 2006, 5, 541–544.
Ziegler, C.; Thiele, S.; Zengerle, R. Direct three-dimensional reconstruction of a nanoporous catalyst layer for a polymer electrolyte fuel cell. J. Power Sources 2011, 196, 2094–2097.
Holzer, L.; Muench, B.; Wegmann, M.; Gasser, P.; Flatt, R. J. FIB-nanotomography of particulate systems—Part Ⅰ: Particle shape and topology of interfaces. J. Amer. Ceram. Soc. 2006, 89, 2577–2585.
Abramoff, M. D.; Magalhaes, P. J.; Ram, S. J. Image processing with ImageJ. Biophoton. Int. 2004, 11, 36–43.
Thevenaz, P.; Ruttimann, U. E.; Unser, M. A pyramid approach to subpixel registration based on intensity. IEEE Trans. Image Process. 1998, 7, 27–41.
Pal, N. R.; Pal, S. K. A review on image segmentation techniques. Pattern Recog. 1993, 26, 1277–1294.
Munch, B.; Gasser, P.; Holzer, L.; Flatt, R. FIB-Nanotomography of particulate systems—Part Ⅱ: Particle recognition and effect of boundary truncation. J. Amer. Ceram. Soc. 2006, 89, 2586–2595.
Ohser, J.; Mücklich, F. Statistical Analysis of Microstructures in Materials Science; John Wiley: New York, 2000.
Wilson, J. R.; Cronin, J. S.; Barnett, S. A.; Harris, S. J. Measurement of three-dimensional microstructure in a LiCoO2 positive electrode J. Power Sources 2011, 196, 3443–3447.
Fischer, A.; Jindra, J.; Wendt, H. Porosity and catalyst utilization of thin layer cathodes in air operated PEM-fuel cells. J. Appl. Electrochem. 1998, 28, 277–282.
Delerue, J. F.; Perrier, E.; Yu, Z. Y.; Velde, B. New algorithms in 3D image analysis and their application to the measurement of a spatialized pore size distribution in soils. Phys. Chem Earth A: Solid Earth Geodesy 1999, 24, 639–644.
Soboleva, T.; Zhao, X.; Malek, K.; Xie, Z.; Navessin, T.; Holdcroft, S. On the micro-, meso-, and macroporous structures of polymer electrolyte membrane fuel cell catalyst layers. ACS Appl. Mater. Interf. 2010, 2, 375–384.
Karniadakis, G.; Beskok, A.; Aluru, N. R. Microflows and Nanoflows: Fundamentals and Simulation; Springer Verlag: Berlin, 2005.
Schaaf, S. A.; Chambré, P. L. Flow of Rarefied Gases; Princeton University Press: Princeton, 1961.
Gad-El-Hak, M. Gas and liquid transport at the microscale. Heat Transf. Eng. 2006, 27, 13–29.
Oran, E. S.; Oh, C. K.; Cybyk, B. Z. Direct simulation Monte Carlo: Recent advances and applications. Annu. Rev. Fluid Mech. 1998, 30, 403–441.
Shen, C.; Tian, D. B.; Xie, C.; Fan, J. Examination of the LBM in simulation of microchannel flow in transitional regime. Nanoscale Microscale Thermophys. Eng. 2004, 8, 423–432.
Kim, S. H.; Pitsch, H.; Boyd, I. D. Lattice Boltzmann modeling of multicomponent diffusion in narrow channels. Phys. Rev. E 2009, 79, 16702.
Zalc, J. M.; Reyes, S. C.; Iglesia, E. Monte Carlo simulations of surface and gas phase diffusion in complex porous structures. Chem. Eng. Sci. 2003, 58, 4605–4617.
Johnson, R. W. The Handbook of Fluid Dynamics; Springer: Heidelberg, 1998.
Cheng, J. T.; Giordano, N. Fluid flow through nanometer-scale channels. Phys. Rev. E 2002, 65, 31206.
Raviv, U.; Laurat, P.; Klein, J. Fluidity of water confined to subnanometre films. Nature 2001, 413, 51–54.
Raviv, U.; Klein, J. Fluidity of bound hydration layers. Science 2002, 297, 1540–1543.
Leng, Y.; Cummings, P. T. Fluidity of hydration layers nanoconfined between mica surfaces. Phys. Rev. Lett. 2005, 94, 26101.
Thomas, J. A.; McGaughey, A. J. H. Water flow in carbon nanotubes: Transition to subcontinuum transport. Phys. Review Lett. 2009, 102, 184502.
Bocquet, L.; Charlaix, E. Nanofluidics, from bulk to interfaces. Chem. Soc. Rev. 2010, 39, 1073–1095.
Huang, D. M.; Sendner, C.; Horinek, D.; Netz, R. R.; Bocquet, L. Water slippage versus contact angle: A quasiuniversal relationship. Phys. Rev. Lett. 2008, 101, 226101.
Sendner, C.; Horinek, D.; Bocquet, L.; Netz, R. R. Interfacial water at hydrophobic and hydrophilic surfaces: Slip, viscosity, and diffusion. Langmuir 2009, 25, 10768–10781.
Tandon, V.; Kirby, B. J. Zeta potential and electroosmotic mobility in microfluidic devices fabricated from hydro-phobic polymers: 2. Slip and interfacial water structure. Electrophoresis 2008, 29, 1102–1114.
Jawhari, T.; Roid, A.; Casado, J. Raman spectroscopic characterization of some commercially available carbon black materials. Carbon 1995, 33, 1561–1565.
Mattia, D.; Gogotsi, Y. Review: Static and dynamic behavior of liquids inside carbon nanotubes. Microfluid. Nanofluid. 2008, 5, 289–305.
Bass, M.; Berman, A.; Singh, A.; Konovalov, O.; Freger, V. Surface structure of Nafion in vapor and liquid. J. Phys. Chem. B 2010, 114, 3784–3790.
