Electrocatalysis simulations

Wang LL, Tanb TL, Johnson DD (2015) Nanoalloy electrocatalysis simulating cyclic voltammetry from configurational thermodynamics with adsorbates. Phys Chem Chem Phys 17 28103-28111... 

First-Principles Simulation of the Active Sites and Reaction Environment in Electrocatalysis... 

Computational efforts using DPT calculations as well as kinetic modeling of reactivities based on Monte Carlo simulations or mean field mefh-ods have been employed to study elementary processes on Pt surfaces. 2 228 Unraveling systematic trends in structure versus reactivity relations remains a formidable challenge due to fhe complex nafure of sfrucfural effects in electrocatalysis. 

In this chapter, the focus will be on trends in electrocatalysis of the water-splitting reaction or the oxygen evolution reaction (OER), which is the reaction at the anode side in an electrolysis cell. Furthermore, simple framework for addressing OER applying DFT simulations will be presented. For further reading, there are two previous book chapters where the approach has been reviewed [3, 4],... 

Catalysis and Electrocatalysis at Nanoparticle Surfaces reflects many of the new developments of catalysis, surface science, and electrochemistry. The first three chapters indicate the sophistication of the theory in simulating catalytic processes that occur at the solid-liquid and solid-gas interface in the presence of external potential. The first chapter, by Koper and colleagues, discusses the theory of modeling of catalytic and electrocatalytic reactions. This is followed by studies of simulations of reaction kinetics on nanometer-sized supported catalytic particles by Zhdanov and Kasemo. The final theoretical chapter, by Pacchioni and Illas, deals with the electronic structure and chemisorption properties of supported metal clusters. 

The next section gives a brief overview of the main computational techniques currently applied to catalytic problems. These techniques include ab initio electronic structure calculations, (ab initio) molecular dynamics, and Monte Carlo methods. The next three sections are devoted to particular applications of these techniques to catalytic and electrocatalytic issues. We focus on the interaction of CO and hydrogen with metal and alloy surfaces, both from quantum-chemical and statistical-mechanical points of view, as these processes play an important role in fuel-cell catalysis. We also demonstrate the role of the solvent in electrocatalytic bondbreaking reactions, using molecular dynamics simulations as well as extensive electronic structure and ab initio molecular dynamics calculations. Monte Carlo simulations illustrate the importance of lateral interactions, mixing, and surface diffusion in obtaining a correct kinetic description of catalytic processes. Finally, we summarize the main conclusions and give an outlook of the role of computational chemistry in catalysis and electrocatalysis. 

M.T. M. Koper, Numerical simulation of electrocatalytic processes, in Handbook of Fuel Cells, Electrocatalysis, John Wiley and Sons, Chichester, 2003, Vol. 2. 

Sufficiently far from equilibrium, which is the only interesting regime for current generation, the Tafel law (129), (130) with effective parameters is used in the simulations. Measurements performed on model electrocatalysts suggest different values for these parameters depending on the particular catalysts used or just their different structure. The mesoscopic effects in electrocatalysis are the hot topic nowadays [127, 187-189] and they are probable candidates for one of the reasons of this variance. The main cause of this variance may be associated with the complicated interplay between adsorption and reaction stages, and a modeler interested in fuel... 

There are about 30 electro-organic synthesis processes thought to be in production and 100 additional ones that have been demonstrated to be feasible on bench scale. In recent years electrocatalysis has been shown to have significant promise in such reactions in many cases, these simulate biological processes and show equivalent selectivity. 

In this section, we discuss anion and OH coadsorption on Pt(l 11) surface to elucidate the effect of competitive adsorption on CO oxidation electrocatalysis. We first perform coadsorption simulations to understand base voltam-mograms, i.e., in the absence of CO oxidation. Next, we show the effect of anions on CO electrooxidation by performing simulations of CO stripping voltammetry, where a monolayer of CO is oxidized by a potential sweep. 

Kalimuthu et al. reported an electrochemical study of EbDH where the enzyme was immobilized on a 5-(4 -pyridinyl)-l,3,4-oxadiazole-2-thiol modified gold electrode and trapped under a membrane. No direct electrochemistry of EbDH was observed, but in the presence of ferrocenium methanol as an effective artificial electron acceptor mediated electrocatalysis of EbDH was demonstrated with its native substrate ethylbenzene (Figure 5.32A) and also the related substrate p-ethylphenol (Figure 5.32B). The catalytic system was modelled by electrochemical simulation across a range of sweep rates and concentrations of substrate and mediator. 

The first three parts approach the classic aspects of electrochemistry on a BA/master s degree level. The fourth part touches on cutting-edge developments in the field of modern research (electrochemistry of solids, conducting polymers, physical methods for analysis, electrocatalysis, photoelectrochemistry, bioelectrochemistry, electrokinetics, interfaces between immisicible liquids, numerical simulations and nanoelectrochemistry, etc.)... 

Keith JA, Jacob T (2010) Computational simulations on the oxygen reduction reaction in electrochemical. In Balbuena PB, Subramanian VR (eds) Theory and experiment in electrocatalysis. Springer, New York, pp 89-132... 

Chapters 7-12 focus on the electrocatalysis of carbon-based non-precious metal catalysts. The unique properties and fuel cell applications of various carbon based catalysts are intensively discussed in these chapters. Chapter 7 summarizes the fundamental studies on the electrocatalytic properties of metallomacrocyclic and other non-macrocyclic complexes. Chapter 8 and 9 review the progress made in the past 5 years of pyrolyzed carbon-supported nitrogen-coordinated transition metal complexes. Chapter 10 gives a comprehensive discussion on the role of transitional metals in the ORR electrocatalysts in acidic medium. Chapter 11 introduces modeling tools such as density functional theory (DPT) and ah initio molecular dynamics (AIMD) simulation for chemical reaction studies. It also presents a theoretical point of view of the ORR mechanisms on Pt-based catalysts, non-Pt metal catalysts, and non-precious metal catalysts. Chapter 12 presents an overview on recent progresses in the development of carbon-based metal-free ORR electrocatalysts, as well as the correlation between catalyst structure and their activities. 

Electrocatalysis - Basic Concepts, Theoretical Treatments in Electrocatalysis via DFT-Based Simulations... 

Electrocatalysis - Basic Concepts, Theoretical Treatments in Electrocatalysis via DFT-Based Simulations, Fig. 1 A core-shell model for a DFT simulation of an Ir shell and a Ni core (Courtesy of the scanning transmission electron microscopy (STEM) image from Drs. Kurian A. Kuttiyiel and Dong Su)... 

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