Abstract
Reaction–diffusion processes in multiscale catalytic porous media are found in a wide range of scientific areas as, for example, electrochemical energy conversion and storage devices, geological systems and bioengineering. The dependency of effective transport properties on reaction rate has been long debated in the literature, and traditionally ignored in emerging fields, such as polymer electrolyte fuel cells (PEFCs). In this work, a 1D upscaling method is presented to evaluate the effective properties (effective diffusivity and catalyst utilization) of PEFC catalyst layers featuring first-order kinetics. Unlike Whitaker’s closure method, the present algorithm is easy to implement and well suited for porous media with arbitrarily complex 3D geometries. The numerical results show that the normalized effective diffusivity and catalyst utilization are not passive geometrical properties but are influenced by the reaction–diffusion coupling when the Thiele modulus is higher than 1. This effect can be important at high current densities in the cathode catalyst layer of state-of-the-art PEFCs.
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Abbreviations
- \( A_{\gamma \kappa } \) :
-
Solid–fluid interface
- \( {\mathbf{b}} \) :
-
Closure variable vector solves Eq. (8) (m)
- \( {\mathbf{b}}_{rx} \) :
-
Closure variable vector solves Eq. (9) (m)
- \( {\mathbf{b}}_{\gamma } \) :
-
Closure variable vector solves Eq. (10) (m)
- \( c \) :
-
Mole concentration (mol/m3)
- \( C \) :
-
Macroscopic superficial concentration (mol/m3)
- \( c^{*} \) :
-
Dimensionless concentration
- \( \left\langle c \right\rangle^{\gamma } \) :
-
Volume-averaged concentration in \( \gamma \) phase (mol/m3)
- \( c_{{{\text{O}}_{2} }}^{\text{cl}} \) :
-
Oxygen concentration in catalyst layer (mol/m3)
- \( c_{{{\text{O}}_{2} }}^{\text{in}} \) :
-
Oxygen concentration in the inlet of the channel (mol/m3)
- \( c_{\text{g}} \) :
-
Overall gas concentration in the inlet of the channel (mol/m3)
- \( c_{{{\text{H}}_{2} {\text{O}}}} \) :
-
Vapor concentration in the inlet of the channel (mol/m3)
- \( D \) :
-
Bulk diffusivity (m2/s)
- \( D_{\text{solid}} \) :
-
Diffusivity in solid phase (m2/s)
- \( D_{\text{eff}} \) :
-
Effective diffusivity (m2/s)
- \( {\mathbf{D}}_{\text{diff}} \) :
-
Passive effective diffusion coefficient which is independent of reaction (m2/s)
- \( {\mathbf{D}}_{\text{eff}} \) :
-
Effective diffusivity tensor (m2/s)
- \( {\mathbf{D}}_{rx} \) :
-
Diffusion-like coefficient which depends on reaction rate (m2/s)
- \( F \) :
-
Faraday’s constant (C/mol)
- \( {\mathbf{I}} \) :
-
Identity tensor
- \( j \) :
-
Current density (A/m2)
- \( j_{\text{critical}} \) :
-
Critical current density (A/m2)
- \( k \) :
-
Reaction rate coefficient (s−1)
- \( k_{\text{eff}} \) :
-
Effective reaction rate coefficient (s−1)
- \( {\mathbf{l}}_{i} \) :
-
Unit cell lattice vectors, \( i \) = 1, 2, 3 (m)
- \( L \) :
-
Thickness between inlet and outlet boundaries (m)
- \( L_{\text{eff}} \) :
-
Length of the tortuous pathway (m)
- \( {\mathbf{n}}_{\gamma \kappa } \) :
-
Unit normal vector directed from the fluid to the solid phase
- \( M \) :
-
Molecular weight (kg/mol)
- \( N \) :
-
Superficial diffusive flux (mol/m2s)
- \( N_{{{\text{O}}_{2} }} \) :
-
Diffusive oxygen flux (mol/m2s)
- \( p_{\text{g}} \) :
-
Gas pressure (Pa)
- \( p_{{{\text{H}}_{2} {\text{O}}}}^{\text{sat}} \) :
-
Vapor pressure of water (Pa)
- \( {\mathbf{r}} \) :
-
Position vector directed from the origin to a point in the averaging domain (m)
- \( R \) :
-
Reaction rate (mol/m3s)
- \( R_{{{\text{O}}_{2} }} \) :
-
Overall oxygen mass transport resistance between inlet of the channel and the catalyst layer (s/m)
- \( R_{u} \) :
-
Gas constant (J/mol K)
- \( T \) :
-
Temperature (K)
- \( U_{\text{eff}} \) :
-
Utilization factor
- \( V_{\text{total}} \) :
-
Total volume of the porous material (m3)
- \( V_{\text{fluid}} \) :
-
Volume of fluid space (m3)
- \( V_{\gamma } \) :
-
Volume of \( \gamma \) phase (m3)
- \( {\mathbf{x}} \) :
-
Position vector directed from the origin to the averaging domain center (m)
- \( z \) :
-
Coordinate in z-direction (m)
- \( z^{*} \) :
-
Dimensionless z-coordinate
- \( \rho \) :
-
Gas mixture density (kg/m3)
- \( \omega \) :
-
Mass fraction
- ε :
-
Porosity
- \( \tau \) :
-
Tortuosity factor
- \( \phi \) :
-
Thiele modulus
- \( \phi_{\text{eff}} \) :
-
Effective Thiele modulus
- \( \varOmega_{\gamma } \) :
-
Domain occupied by \( \gamma \) phase
- \( \partial \varOmega_{\gamma \kappa } \) :
-
Domain occupied by solid–fluid interface
References
Baker, D.R., Caulk, D.A., Neyerlin, K.C., Murphy, M.W.: Measurement of oxygen transport resistance in PEM fuel cells by limiting current methods. J. Electrochem. Soc. 156, B991–B1003 (2009)
Bear, J., Buchlin, J.-M. (eds.): Modelling and Applications of Transport Phenomena in Porous Media. Kluwer Academic Publishers, Dordrecht (1991)
Bird, R.B., Lightfoot, E.N., Stewart, W.E.: Transport Phenomena. Wiley, New York (2002)
Bosomoiu, M., Tsotridis, G., Bednarek, T.: Study of effective transport properties of fresh and aged gas diffusion layers. J. Power Sources 285, 568–579 (2015)
Dadvar, M., Sahimi, M.: The effective diffusivities in porous media with and without nonlinear reactions. Chem. Eng. Sci. 62, 1466–1476 (2007)
Debe, M.K.: Electrocatalyst approaches and challenges for automotive fuel cells. Nature 486, 43 (2012)
Eller, J., Roth, J., Marone, F., Stampanoni, M., Büchi, F.N.: Operando properties of gas diffusion layers: saturation and liquid permeability. J. Electrochem. Soc. 164, F115–F126 (2017)
Epstein, N.: On tortuosity and the tortuosity factor in flow and diffusion through porous media. Chem. Eng. Sci. 44, 777–779 (1989)
Epting, W.K., Litster, S.: Effects of an agglomerate size distribution on the PEFC agglomerate model. Int. J. Hydrogen Energy 37, 8505–8511 (2012)
Fang, W.-Z., Tang, Y.-Q., Chen, L., Kang, Q.-J., Tao, W.-Q.: Influences of the perforation on effective transport properties of gas diffusion layers. Int. J. Heat Mass Transf. 126, 243–255 (2018)
García-Ochoa, F., Santos, A.: Effective diffusivity under inert and reaction conditions. Chem. Eng. Sci. 49, 3091–3102 (1994)
García-Salaberri, P.A., Hwang, G., Vera, M., Weber, A.Z., Gostick, J.T.: Effective diffusivity in partially-saturated carbon-fiber gas diffusion layers: effect of through-plane saturation distribution. Int. J. Heat Mass Transf. 86, 319–333 (2015a)
García-Salaberri, P.A., Gostick, J.T., Hwang, G., Weber, A.Z., Vera, M.: Effective diffusivity in partially-saturated carbon-fiber gas diffusion layers: effect of local saturation and application to macroscopic continuum models. J. Power Sources 296, 440–453 (2015b)
García-Salaberri, P.A., Sánchez, D.G., Boillat, P., Vera, M., Friedrich, K.A.: Hydration and dehydration cycles in polymer electrolyte fuel cells operated with wet anode and dry cathode feed: a neutron imaging and modeling study. J. Power Sources 359, 634–655 (2017a)
García-Salaberri, P.A., Gostick, J.T., Zenyuk, I.V., Hwang, G., Vera, M., Weber, A.Z.: On the limitations of volume-averaged descriptions of gas diffusion layers in the modeling of polymer electrolyte fuel cells. ECS Trans. 80, 133–143 (2017b)
García-Salaberri, P.A., Zenyuk, I.V., Shum, A.D., Hwang, G., Vera, M., Weber, A.Z., Gostick, J.T.: Analysis of representative elementary volume and through-plane regional characteristics of carbon-fiber papers: diffusivity, permeability and thermal/electrical conductivity. Int. J. Heat Mass Transf. 127, 687–703 (2018)
Gröger, O., Gasteiger, H.A., Suchsland, J.-P.: Review—electromobility: batteries or fuel cells? J. Electrochem. Soc. 162, A2605–A2622 (2015)
Gürsoy, D., De Carlo, F., Xiao, X., Jacobsen, C.: TomoPy: a framework for the analysis of synchrotron tomographic data. J. Synchrotron Radiat. 21, 1188–1193 (2014)
Hao, L., Moriyama, K., Gu, W., Wang, C.-Y.: Modeling and experimental validation of pt loading and electrode composition effects in PEM fuel cells. J. Electrochem. Soc. 162, F854–F867 (2015)
Kamitaka, Y., Takeshita, T., Morimoto, Y.: MgO-templated mesoporous carbon as a catalyst support for polymer electrolyte fuel cells. Catalysts 8, 230 (2018)
Karaki, M., Hallal, A., Younes, R., Trochu, F., Lafon, P., Hayek, A., Kobeissy, A., Fayad, A.: A comparative analytical, numerical and experimental analysis of the microscopic permeability of fiber bundles in composite materials. Int. J. Compos. Mater. 7, 82–102 (2017)
Kim, S.H., Pitsch, H.: Reconstruction and effective transport properties of the catalyst layer in PEM fuel cells. J. Electrochem. Soc. 156, B673–B681 (2009)
Lange, K.J., Sui, P.-C., Djilali, N.: Pore scale simulation of transport and electrochemical reactions in reconstructed PEMFC catalyst layers. J. Electrochem. Soc. 157, B1434–B1442 (2010)
Litster, S., Epting, W.K., Wargo, E.A., Kalidindi, S.R., Kumbur, E.C.: Morphological analyses of polymer electrolyte fuel cell electrodes with nano-scale computed tomography imaging. Fuel Cells 13, 935–945 (2013)
Lugo-Méndez, H.D., Valdés-Parada, F.J., Porter, M.L., Wood, B.D., Ochoa-Tapia, J.A.: Upscaling diffusion and nonlinear reactive mass transport in homogeneous porous media. Transp. Porous Media 107, 683–716 (2015)
Mukherjee, P.P., Wang, C.-Y.: Stochastic microstructure reconstruction and direct numerical simulation of the PEFC catalyst layer. J. Electrochem. Soc. 153, A840–A849 (2006)
Normile, S.J., Sabarirajan, D.C., Calzada, O., De Andrade, V., Xiao, X., Mandal, P., Parkinson, D.Y., Serov, A., Atanassov, P., Zenyuk, I.V.: Direct observations of liquid water formation at nano- and micro-scale in platinum group metal-free electrodes by operando X-ray computed tomography. Mater. Today Energy 9, 187–197 (2018)
O’Hayre, R., Cha, S.-W., Prinz, F.B., Colella, W.: Fuel Cell Fundamentals. Wiley, New York (2016)
Owejan, J.P., Trabold, T.A., Mench, M.M.: Oxygen transport resistance correlated to liquid water saturation in the gas diffusion layer of PEM fuel cells. Int. J. Heat Mass Transf. 71, 585–592 (2014)
Park, S.H., Kim, Y.G.: The effect of chemical reaction on effective diffusivity within biporous catalysts—I: theoretical development. Chem. Eng. Sci. 39, 523–531 (1984)
Pavlicek, R., Barton, S.C., Leonard, N., Romero, H., McKinney, S., McCool, G., Serov, A., Abbott, D., Atanassov, P., Mukerjee, S.: Resolving challenges of mass transport in non Pt-group metal catalysts for oxygen reduction in proton exchange membrane fuel cells. J. Electrochem. Soc. 165, F589–F596 (2018)
Ryan, D., Carbonell, R.G., Whitaker, S.: Effective diffusivities for catalyst pellets under reactive conditions. Chem. Eng. Sci. 35, 10–16 (1980)
Sadeghi, M.A., Aghighi, M., Barralet, J., Gostick, J.T.: Pore network modeling of reaction-diffusion in hierarchical porous particles: the effects of microstructure. Chem. Eng. J. 330, 1002–1011 (2017)
Sahimi, M.: Diffusion-controlled reactions in disordered porous media—I. Uniform distribution of reactants. Chem. Eng. Sci. 43, 2981–2993 (1988)
Salejova, G., Grof, Z., Solcova, O., Schneider, P., Kosek, J.: Strategy for predicting effective transport properties of complex porous structures. Comput. Chem. Eng. 35, 200–211 (2011)
Schindelin, J., Arganda-Carreras, I., Frise, E., Kaynig, V., Longair, M., Pietzsch, T., Preibisch, S., Rueden, C., Saalfeld, S., Schmid, B., Tinevez, J.-Y., White, D.J., Hartenstein, V., Eliceiri, K., Tomancak, P., Cardona, A.: Fiji: an open-source platform for biological-image analysis. Nat. Methods 9, 676–682 (2012)
Schneider, C.A., Rasband, W.S., Eliceiri, K.W.: NIH Image to ImageJ: 25 years of image analysis. Nat. Methods 9, 671–675 (2012)
Serov, A., Shum, A.D., Xiao, X., De Andrade, V., Artyushkova, K., Zenyuk, I.V., Atanassov, P.: Nano-structured platinum group metal-free catalysts and their integration in fuel cell electrode architectures. Appl. Catal. B Environ. 237, 1139–1147 (2018)
Steinbach, A.J., Allen, J.S., Borup, R.L., Hussey, D.S., Jacobson, D.L., Komlev, A., Kwong, A., MacDonald, J., Mukundan, R., Pejsa, M.J., Roos, M., Santamaria, A.D., Sieracki, Spernjak D., Zenyuk, I.V., Weber, A.Z .: Anode-design strategies for improved performance of polymer-electrolyte fuel cells with ultra-thin electrodes. Joule 2, 1297–1312 (2018)
Sun, W., Peppley, B.A., Karan, K.: An improved two-dimensional agglomerate cathode model to study the influence of catalyst layer structural parameters. Electrochim. Acta 50, 3359–3374 (2005)
Tanno, K., Kurose, R., Michioka, T., Makino, H., Komori, S.: Direct numerical simulation of flow and surface reaction in de-NOx catalyst. Adv. Powder Technol. 24, 879–885 (2013)
Toei, R., Okazaki, M., Nakanishi, K., Kondo, Y., Hayashi, M., Shiozaki, Y.: Effective diffusivity of a porous catalyst with and without chemical reaction. J. Chem. Eng. Jpn. 6, 50–58 (1973)
Valdes-Parada, F.J., Alvarez-Ramirez, J.: On the effective diffusivity under chemical reaction in porous media. Chem. Eng. Sci. 65, 4100–4104 (2010)
Wakao, N., Kimura, H., Shibata, M.: Kinetic studies and effective diffusivities in para to ortho hydrogen conversion reaction. J. Chem. Eng. Jpn. 2, 51–54 (1969)
Wang, G., Mukherjee, P.P., Wang, C.-Y.: Direct numerical simulation (DNS) modeling of PEFC electrodes: part I. Regular microstructure. Electrochim. Acta 51, 3139–3150 (2006a)
Wang, G., Mukherjee, P.P., Wang, C.-Y.: Direct numerical simulation (DNS) modeling of PEFC electrodes: part II. Random microstructure. Electrochim. Acta 51, 3151–3160 (2006b)
Wang, C., Cheng, X., Lu, J., Shen, S., Yan, X., Yin, J., Wei, G., Zhang, J.: The experimental measurement of local and bulk oxygen transport resistances in the catalyst layer of proton exchange membrane fuel cells. J. Phys. Chem. Lett. 8, 5848–5852 (2017)
Weber, A.Z., Mench, M.M., Meyers, J.P., Ross, P.N., Gostick, J.T., Liu, Q.: Redox flow batteries: a review. J. Appl. Electrochem. 41, 1137 (2011)
Weber, A.Z., Borup, R.L., Darling, R.M., Das, P.K., Dursch, T.J., Gu, W., Harvey, D., Kusoglu, A., Litster, S., Mench, M.M., Mukundan, R., Owejan, J.P., Pharoah, J.G., Secanell, M., Zenyuk, I.V.: A critical review of modeling transport phenomena in polymer-electrolyte fuel cells. J. Electrochem. Soc. 161, F1254–F1299 (2014)
Whitaker, S.: The Method of Volume Averaging. Springer, Dordrecht (1999)
Zarandi, M.A.F., Pillai, K.M., Barari, B.: Flow along and across glass-fiber wicks: testing of permeability models through experiments and simulations. AIChE J. 64, 3491–3501 (2018)
Zenyuk, I.V., Das, P.K., Weber, A.Z.: Understanding impacts of catalyst-layer thickness on fuel-cell performance via mathematical modeling. J. Electrochem. Soc. 163, F691–F703 (2016a)
Zenyuk, I.V., Parkinson, D.Y., Connolly, L.G., Weber, A.Z.: Gas-diffusion-layer structural properties under compression via X-ray tomography. J. Power Sources 328, 364–376 (2016b)
Acknowledgements
The work was supported by NSF CAREER award #1652445. This research used resources of the Advanced Photon Source, a US Department of Energy (DOE) Office of Science User Facility operated for the DOE Office of Science by Argonne National Laboratory under Contract No. DE-AC02-06CH11357. Pablo A. García-Salaberri thanks support from Project ENE2015-68703-C2-1-R (MINECO/FEDER, UE), the research grant ‘Ayudas a la Investigación en Energía y Medio Ambiente’ of the Spanish Iberdrola Foundation and the US-Spain Fulbright Commission.
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Liu, J., García-Salaberri, P.A. & Zenyuk, I.V. The Impact of Reaction on the Effective Properties of Multiscale Catalytic Porous Media: A Case of Polymer Electrolyte Fuel Cells. Transp Porous Med 128, 363–384 (2019). https://doi.org/10.1007/s11242-019-01252-8
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DOI: https://doi.org/10.1007/s11242-019-01252-8