Molecular Simulation Method Development and Implementation for Fuel Cell Catalyst Layers PDF Download

Author: Peter Vanya
Publisher:
ISBN:
Category :
Languages : en
Pages :

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Author: Michael Eikerling
Publisher: CRC Press
ISBN: 1439854068
Category : Science
Languages : en
Pages : 567

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The book provides a systematic and profound account of scientific challenges in fuel cell research. The introductory chapters bring readers up to date on the urgency and implications of the global energy challenge, the prospects of electrochemical energy conversion technologies, and the thermodynamic and electrochemical principles underlying the op

Author: Jiujun Zhang
Publisher: Springer Science & Business Media
ISBN: 1848009364
Category : Technology & Engineering
Languages : en
Pages : 1147

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Proton exchange membrane (PEM) fuel cells are promising clean energy converting devices with high efficiency and low to zero emissions. Such power sources can be used in transportation, stationary, portable and micro power applications. The key components of these fuel cells are catalysts and catalyst layers. “PEM Fuel Cell Electrocatalysts and Catalyst Layers” provides a comprehensive, in-depth survey of the field, presented by internationally renowned fuel cell scientists. The opening chapters introduce the fundamentals of electrochemical theory and fuel cell catalysis. Later chapters investigate the synthesis, characterization, and activity validation of PEM fuel cell catalysts. Further chapters describe in detail the integration of the electrocatalyst/catalyst layers into the fuel cell, and their performance validation. Researchers and engineers in the fuel cell industry will find this book a valuable resource, as will students of electrochemical engineering and catalyst synthesis.

Author: Tatsuhiro Okada
Publisher: Springer Science & Business Media
ISBN: 3540707581
Category : Science
Languages : en
Pages : 450

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Over the past decade the topic of energy and environment has been ackno- edged among many people as a critical issue to be solved in 21st century since the Kyoto Protocol came into e?ect in 1997. Its political recognition was put forward especially at Heiligendamm in 2007, when the e?ect of carbon dioxide emission and its hazard in global climate were discussed and shared univ- sallyascommonknowledge.Controllingtheglobalwarmingintheeconomical framework of massive development worldwide through this new century is a very challenging problem not only among political, economical, or social c- cles but also among technological or scienti?c communities. As long as the humans depend on the combustion of fossil for energy resources, the waste heat exhaustion and CO emission are inevitable. 2 In order to establish a new era of energy saving and environment benign society, which is supported by technologies and with social consensus, it is important to seek for a framework where new clean energy system is inc- porated as infrastructure for industry and human activities. Such a society strongly needs innovative technologies of least CO emission and e?cient en- 2 ergy conversion and utilization from remaining fossil energies on the Earth. Energy recycling system utilizing natural renewable energies and their c- version to hydrogen may be the most desirable option of future clean energy society. Thus the society should strive to change its energy basis, from foss- consuming energy to clean and recycling energy.

Author: Amin Nouri Khorasani
Publisher:
ISBN:
Category : Catalysts
Languages : en
Pages : 198

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Book Description
Ionomer-free ultrathin catalyst layers have shown promise to enhance the performance and reduce the platinum loading of catalyst layers in polymer electrolyte fuel cell. The nanostructure of a catalyst layer affects the distribution and diffusion of reactants, and consequently its effectiveness factor. We employed classical molecular dynamics to simulate a catalyst layer pore as a water-filled channel with faceted walls, and investigated the effect of channel geometry and charging on hydronium ion and water distribution and diffusion in the channel. Equilibrium hydronium ion distribution profiles on the catalyst channel were obtained to calculate the effect of channel structure on the electrostatic effectiveness factor of the channel. Furthermore, we calculated the self-diffusion coefficient and interfacial water structure in the model channel. Results on proton concentration, diffusion and kinetics are discussed in view of catalyst layer performance.

Author: Mamoru Ishii
Publisher: Springer Science & Business Media
ISBN: 0387291873
Category : Technology & Engineering
Languages : en
Pages : 462

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This book has been written for graduate students, scientists and engineers who need in-depth theoretical foundations to solve two-phase problems in various technological systems. Based on extensive research experiences focused on the fundamental physics of two-phase flow, the authors present the detailed theoretical foundation of multi-phase flow thermo-fluid dynamics as they apply to a variety of scenarios, including nuclear reactor transient and accident analysis, energy systems, power generation systems and even space propulsion.

Author: Timothy E. Lipman
Publisher: Springer
ISBN: 9781493977888
Category : Technology & Engineering
Languages : en
Pages : 0

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The expected end of the “oil age” will lead to increasing focus and reliance on alternative energy conversion devices, among which fuel cells have the potential to play an important role. Not only can phosphoric acid and solid oxide fuel cells already efficiently convert today’s fossil fuels, including methane, into electricity, but other types of fuel cells, such as polymer electrolyte membrane fuel cells, have the potential to become the cornerstones of a possible future hydrogen economy. This handbook offers concise yet comprehensive coverage of the current state of fuel cell research and identifies key areas for future investigation. Internationally renowned specialists provide authoritative introductions to a wide variety of fuel cell types and hydrogen production technologies, and discuss materials and components for these systems. Sustainability and marketing considerations are also covered, including comparisons of fuel cells with alternative technologies.

Author:
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Category :
Languages : en
Pages :

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The cathode catalyst layer within a proton-exchange-membrane fuel cell is the most complex and critical, yet least understood, layer within the cell. The exact method and equations for modeling this layer are still being revised and will be discussed in this paper, including a 0.8 reaction order, existence of Pt oxides, possible non-isopotential agglomerates, and the impact of a film resistance towards oxygen transport. While the former assumptions are relatively straightforward to understand and implement, the latter film resistance is shown to be critically important in explaining increased mass-transport limitations with low Pt-loading catalyst layers. Model results demonstrate agreement with experimental data that the increased oxygen flux and/or diffusion pathway through the film can substantially decrease performance. Also, some scale-up concepts from the agglomerate scale to the more macroscopic porous-electrode scale are discussed and the resulting optimization scenarios investigated.

Author: Luigi Gurreri
Publisher: MDPI
ISBN: 3036515305
Category : Technology & Engineering
Languages : en
Pages : 236

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Book Description
Electromembrane processes offer a multitude of applications, allowing for the recovery of water, other products, and energy. This book is a collection of contributions on recent advancements in electromembrane processes attained via experiments and/or models. The first paper is a comprehensive review article on the applications of electrodialysis for wastewater treatment, highlighting current status, technical challenges, and key points for future perspectives. The second paper focuses on ZSM-5 zeolite/PVA mixed matrix CEMs with high monovalent permselectivity for recovering either acid or Li+. The third paper regards direct numerical simulations of electroconvection in an electrodialysis dilute channel with forced flow under potentiodynamic and galvanodynamic regimes. The fourth paper investigates the reasons for the formation and properties of soliton-like charge waves in overlimiting conditions. The fifth paper focuses on the characterization of AEMs functionalized by surface modification via poly(acrylic) acid yielding monovalent permselectivity for reverse electrodialysis. In the sixth paper, CFD simulations of reverse electrodialysis systems are performed. The seventh paper proposes an integrated membrane process, including electrochemical intercalation–deintercalation, for the preparation of Li2CO3 from brine with a high Mg2+/Li+ mass ratio. Finally, the eighth paper is a perspective article devoted to the acid–base flow battery with monopolar and bipolar membranes.

Author: Partha P. Mukherjee
Publisher:
ISBN:
Category :
Languages : en
Pages :

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The catalyst layer (CL) plays a crucial role in the overall performance of a polymer electrolyte fuel cell (PEFC) due to the sluggish oxygen reduction reaction as well as transport limitation in the presence of liquid water and ensuing flooding. Nevertheless, it is often treated either as a thin interface or a macrohomogeneous porous layer and the influence of underlying morphology and wetting characteristics on the catalyst layer performance and water transport is ignored. The macroscopic fuel cell models, therefore, employ effective transport properties for reactant and charge transport as well as arbitrary two-phase closure relations for capillary pressure and relative permeability, the experimental measurements of which are exceedingly difficult and might be impossible in the near future. The role of the catalyst layer flooding in the overall cell performance and the mechanisms of liquid water transport/removal from the CL remain unexplored. In order to reveal the underlying structure-performance relationship and to predict reliable closure relations, a pore-scale modeling framework comprising of a stochastic microstructure reconstruction model, an electrochemistry coupled direct numerical simulation (DNS) model and a two-phase lattice Boltzmann (LB) model is developed. The stochastic reconstruction model generates 3-D, statistically meaningful catalyst layer microstructure based on inputs from transmission electron microscope (TEM) images of an actual catalyst layer. Pore-level description of charge and species transport within the complex CL microstructure is achieved through the direct numerical simulation (DNS) model. The main purpose of the DNS model is to unravel the CL compositional influence on the performance and enable composition optimization for better performance. The mesoscopic lattice Boltzmann (LB) model simulates the liquid water transport through the CL microstructure in order to gain insight into the influence of structure on the pore-scale two-phase dynamics as well as to evaluate the two-phase constitutive relations in terms of capillary pressure and relative permeability as functions of liquid water saturation. A quantitative estimate of the detrimental effect of liquid water on the CL electrochemical performance in terms of the pore blockage and catalytic site coverage effects, which cannot be evaluated experimentally at present, is predicted from the combined LB and DNS models. These transport parameters can be used as reliable closure relations in macroscopic fuel cell models. Furthermore, a macroscopic model of CL flooding is devised based on a simplified structure-wettability representation and a physical description of water and heat balance. The role of evaporation in the CL liquid water saturation distribution and resulting flooding is elucidated. While the primary focus of the pore-scale modeling is to quantitatively estimate the transport parameters along with a detailed structure-transport-performance description, the macroscopic analysis reveals profound inter-relations of adjacent components and operating cell temperature with CL flooding.