This volume provides a thorough overview on the fundamental and applied aspects of the recent developments and advances in the area of alkali metal adsorption on metals and semiconductors. Effects such as surface reconstruction, ordered phases, electronic transitions and surface diffusion are discussed. Coadsorption of alkali metals and molecules on metal surfaces is examined in terms of particle interactions and surface reactivity. Special attention is given to the relationship between coadsorption-studies and heterogeneous catalysis. Other topics reviewed include the study of matrix-isolated alkali metal-molecule complexes and the alkali metal-enhanced surface reactivity of semiconductors. Written by a team of international experts, the work will provide both a stimulus for future research in this field, as well as useful reference material for many years to come.
The Chemical Physics of Solid Surfaces, Volume 6: Coadsorption, Promoters, and Poisons focuses on the processes, reactions, and approaches involved in coadsorption and the functions of promoters and poisons in synthesis and reactions. The selection first offers information on adsorbate-adsorbate interactions on metal surfaces and interaction between alkali metal adsorbates and adsorbed molecules. Discussions focus on coadsorption of alkali metals and other molecules; model experiments of catalyst promotion; effective medium theory; direct and indirect hybridization effects; and elastic interaction between adsorbates. The publication then ponders on coadsorption of carbon monoxide and hydrogen on metal surfaces and adsorption on bimetallic surfaces. The manuscript examines the chemical properties of alloy single crystal surfaces and promotion in ammonia synthesis. Topics include substrate dependence of nitrogen adsorption and ammonia synthesis; effects of promotion on nitrogen dissociation and ammonia synthesis; and theoretical modeling. The text then elaborates on promotion in the Fischer-Tropsch hydrocarbon synthesis, promoters and poisons in the water-gas shift reaction, and strong metal-support interactions. The selection is a recommended reference for physicists and readers interested in coadsorption, promoters, and poisons.
The topics covered in this book include a variety of adsorption and model reaction studies on clean and modified single crystal metal surfaces obtained by means of properly selected surface sensitive techniques. The accent is on the revelation of the physics and chemistry involved in the effects of various modifiers on the adsorptive and reactivity properties of the surface with respect to different reactants. In this book current information that contributes to the fundamental understanding of the effect of additives is summarized. Some of the additives act as promoters, others as poisons, in a number of important catalytic reactions. A description of single- and double-component systems has been obtained by using surface-sensitive techniques, particularly suited for this purpose. For the benefit of the reader, a short summary of the main surface science techniques has been given in Chapter 2. Three general and interrelated topics are reviewed. The first concerns the interaction of electronegative (Cl, S, Se, C, N, O, P) and electropositive (alkali metals) atoms with metal surfaces (Chapter 4). The second topic covers the chemisorptive properties of metal surfaces modified by varying amounts of additives with respect to different reactants (CO, NO, N2, O2, H2, CO2, NH3, H2O and hydrocarbons) (Chapters 5 and 6). In particular the adsorption kinetics and energetics, and the electronic, structural and reactive properties of the coadsorbate systems are considered, whereby particular attention is given to recent surface science studies with well-characterized, single crystal, metal surfaces. In these chapters, special attention is paid to showing the contribution of different factors (the nature and adsorption state of the modifier and the coadsorbed molecule, the structure of the adsorbed layer, the type of interactions in the mixed overlayers, etc.) to the modifier effects. In the discussion of the third topic, model studies of several important catalytic reactions (Fischer-Tropsch synthesis, ammonia synthesis, CO oxidation, water-gas shift synthesis) on modified metal surfaces (Chapter 8) are considered. The book will be particularly useful to scientists who are interested in adsorption phenomena, surface properties and catalysis. It should also prove invaluable to those addressing the questions of condensed matter (surfaces and interfaces), materials science (e.g. corrosion of metals) and electrochemistry.
In eight volumes, Surface and Interface Science covers all fundamental aspects and offers a comprehensive overview of this research area for scientists working in the field, as well as an introduction for newcomers. Volume 5: Solid-Gas Interfaces I Topics covered: Basics of Adsorption and Desorption Surface Microcalorimetry Adsorption of Rare Gases Adsorption of Alkali and Other Electro-Positive Metals Halogen adsorption on metals Adsorption of Hydrogen Adsorption of Water Adsorption of (Small) Molecules on Metal Surfaces Surface Science Approach to Catalysis Adsorption, Bonding and Reactivity of Unsaturated and Multifunctional Molecules Volume 6: Solid-Gas Interfaces II Topics covered: Adsorption of Large Organic Molecules Chirality of Adsorbates Adsorption on Semiconductor Surfaces Adsorption on Oxide Surfaces Oscillatory Surface Reactions Statistical Surface Thermodynamics Theory of the Dynamics at Surfaces Atomic and Molecular Manipulation
The primary goal of this book is to summarize the current level of accumulated knowledge about the physical structure of solid surfaces with emphasis on well-defined surfaces at the gas-solid and vacuum-solid interfaces. The intention is not only to provide a standard reference for practitioners, but also to provide a good starting point for scientists who are just entering the field. The presentation in most of the chapters therefore assumes that the typical reader will have a good undergraduate background in chemistry, physics, or materials science. At the same time, coverage is comprehensive and at a high technical level with emphasis on fundamental physical principles. This first volume in a new series is appropriately devoted to the physical structure of surfaces, knowledge of which will be essential for a complete understanding of electronic properties and dynamical processes, the topics of the next two volumes in the series. The volume is divided into four parts. Part I describes the equilibrium properties of surfaces with emphasis on clean surfaces of bulk materials. Part II provides an introduction to some of the primary experimental methods that are used to determine surface crystal structures. Part III gives an overview of the vast topic of the structure of adsorbed layers. The concluding Part IV deals with the topics of defects in surface structures and phase transitions.
The presence of alkali cations in electrolyte solutions is known to impact the rate of electrocatalytic reactions, though the mechanism of such impact is not conclusively determined. We use density functional theory (DFT) to examine the specific adsorption of alkali cations to fcc(111) electrode surfaces, as specific adsorption may block catalyst sites or otherwise impact surface catalytic chemistry. Solvation of the cation-metal surface structure was investigated using explicit water models. Computed equilibrium potentials for alkali cation adsorption suggest that alkali and alkaline earth cations will specifically adsorb onto Pt(111) and Pd(111) surfaces in the potential range of hydrogen oxidation and hydrogen evolution catalysis in alkaline solutions.This results presented in this thesis are included within "J. N. Mills, I. T. McCrum, and M. J. Janik. "Alkali cation specific adsorption onto fcc (111) transition metal electrodes" Physical Chemistry Chemical Physics 16 (2014) 13699-13707."
