Surface Science

Foundations of Catalysis and Nanoscience

Kurt W. Kolasinski

• Publisher: Wiley
• Year: 2019
• ISBN:
  9781119546610
• Edition: 4
• Topic: Technology & Engineering
• Subtopic: Materials Science
• Index: Technology & Engineering

An updated fourth edition of the text that provides an understanding of chemical transformations and the formation of structures at surfaces

The revised and enhanced fourth edition of Surface Science covers all the essential techniques and phenomena that are relevant to the field. The text elucidates the structural, dynamical, thermodynamic and kinetic principles concentrating on gas/solid and liquid/solid interfaces. These principles allow for an understanding of how and why chemical transformations occur at surfaces. The author (a noted expert on in the field) combines the required chemistry, physics and mathematics to create a text that is accessible and comprehensive.

The fourth edition incorporates new end-of-chapter exercises, the solutions to which are available on-line to demonstrate how problem solving that is relevant to surface science should be performed. Each chapter begins with simple principles and builds to more advanced ones. The advanced topics provide material beyond the introductory level and highlight some frontier areas of study. This updated new edition:

• Contains an expanded treatment of STM and AFM as well as super-resolution microscopy
• Reviews advances in the theoretical basis of catalysis and the use of activity descriptors for rational catalyst design
• Extends the discussion of two-dimensional solids to reflect remarkable advances in their growth and characterization
• Delves deeper into the surface science of electrochemistry and charge transfer reactions
• Updates the "Frontiers and Challenges" sections at the end of each chapter as well as the list of references

Written for students, researchers and professionals, the fourth edition of Surface Science offers a revitalized text that contains the tools and a set of principles for understanding the field. Instructor support material, solutions and PPTs of figures, are available at http://booksupport.wiley.com

1
Surface and Adsorbate Structure

We begin with some order of magnitude estimates and rules of thumb that will be justified in the remainder of this book. These estimates and rules introduce and underpin many of the most important concepts in surface science. The atom density in a solid surface is roughly 10¹⁵ cm⁻² (10¹⁹ m⁻²). The Hertz‐Knudsen equation

(1.0.1)

relates the flux of molecules striking a surface, Z_w, to the pressure (or equivalently the number density). Combining these two, we find that if the probability that a molecule stays on the surface after it strikes it (known as the sticking coefficient s) is unity, then it takes roughly 1 s for a surface to become covered with a film one molecule thick (a monolayer) when the pressure is 1 × 10⁻⁶ Torr (= 1.33 × 10⁻⁶ mbar = 1.33 × 10⁻⁴ Pa). The process of molecules sticking to a surface is called adsorption, a term coined by Kayser in 1881 [1]. If we heat up the surface with a linear temperature ramp, the molecules will eventually leave the surface (desorb) in a well‐defined thermal desorption peak. The rate of desorption at the top of this peak is roughly one monolayer per second. When molecules adsorb via chemical interactions, they tend to stick to well‐defined sites on the surface. An essential difference between surface kinetics and kinetics in other phases is that we need to keep track of the number of empty sites. Creating new surface area is energetically costly and creates a region that differs structurally and in chemical behaviour from the bulk material. Size dependent effects lie at the root of nanoscience. Two of the primary causes of size dependence are quantum confinement and the overwhelming of bulk properties by the contributions from surfaces.

We need to understand the structure of clean and adsorbate‐covered surfaces and use this as a foundation for understanding surface chemical processes. We will use our knowledge of surface structure to develop a new strand of chemical intuition that will allow us to know when we can apply things that we have learned from reaction dynamics in other phases and when we need to develop something completely different to understand reactivity in the adsorbed phase.

What do we mean by surface structure? There are two inseparable aspects to structure: electronic structure and geometric structure. The two aspects of structure are inherently coupled and we should never forget this point. Nonetheless, it is pedagogically helpful to separate these two aspects when we attack them experimentally and in the ways that we conceive of them.

When we speak of structure in surface science we can further subdivide the discussion into that of the clean surface, the surface in the presence of an adsorbate (substrate structure) and that of the adsorbate (adsorbate structure or overlayer structure). That is, we frequently refer to the structure of the first few layers of the substrate with and without an adsorbed layer of dissimilar material on top of it. We can in addition speak of the structure of the adsorbed layer itself. Adsorbate structure refers not only to how the adsorbed molecules are bound with respect to the substrate atoms but also how they are bound with respect to one another.

1.1 Clean surface structure

1.1.1 Ideal flat surfaces

Most of the discussion here centres on transition metal and semiconductor surfaces. First, we consider the type of surface we obtain by truncating the bulk structure of a perfect crystal. The most important crystallographic structures of metals are the face‐centred cubic (fcc), body‐centred cubic (bcc), and hexagonal close‐packed (hcp) structures. Many transition metals of interest in catalysis take up fcc structures under normal conditions. Notable exceptions are Fe, Mo, and W, which assume bcc structures and Co and Ru, which assume hcp structures. The most important structure for elemental (group IV: C, Si, Ge) semiconductors...

Table of contents

• Cover
• Table of Contents
• Preface
• Supplementary Material
• Introduction
• 1 Surface and Adsorbate Structure
• 2 Experimental Probes and Techniques
• 3 Chemisorption, Physisorption, and Dynamics
• 4 Thermodynamics and Kinetics of Adsorption and Desorption
• 5 Liquid Interfaces
• 6 Heterogeneous Catalysis
• 7 Growth and Epitaxy
• 8 Laser and Non‐thermal Chemistry: Photon and Electron Stimulated Chemistry and Atom Manipulation
• Appendix A:Appendix AAbbreviations and Prefixes
• Appendix B: Appendix BSymbolsSymbols
• Appendix C:Appendix CUseful Mathematical ExpressionsUseful Mathematical Expressions
• Index
• End User License Agreement