Surface Science Aspects

Winters H F and Coburn J W 1992 Surface science aspects of etching reactions Surf. Sc/. Rep. 14 161... 

H.F. Winters, J.W. Coburn Surface science aspects of etching reactions. Surf. Sci. Reports 14, 161 (1992)... 

Kasemo, B., and Lausmaa, X, Surface science aspects of inorganic biomaterials. C.R.C. Critical Rev. in Biocompatibility 2, 335-380 (1986). 

PR Schwoebel, I Brodie. Surface-science aspects of vacuum microelectronics. J Vac Sci Technol B 13 1391, 1995. 

Surfaces are investigated with surface-sensitive teclmiques in order to elucidate fiindamental infonnation. The approach most often used is to employ a variety of techniques to investigate a particular materials system. As each teclmique provides only a limited amount of infonnation, results from many teclmiques must be correlated in order to obtain a comprehensive understanding of surface properties. In section A 1.7.5. methods for the experimental analysis of surfaces in vacuum are outlined. Note that the interactions of various kinds of particles with surfaces are a critical component of these teclmiques. In addition, one of the more mteresting aspects of surface science is to use the tools available, such as electron, ion or laser beams, or even the tip of a scaiming probe instrument, to modify a surface at the atomic scale. The physics of the interactions of particles with surfaces and the kinds of modifications that can be made to surfaces are an integral part of this section. 

Wlien a surface is exposed to a gas, the molecules can adsorb, or stick, to the surface. Adsorption is an extremely important process, as it is the first step in any surface chemical reaction. Some of die aspects of adsorption that surface science is concerned with include the mechanisms and kinetics of adsorption, the atomic bonding sites of adsorbates and the chemical reactions that occur with adsorbed molecules. 

How are fiindamental aspects of surface reactions studied The surface science approach uses a simplified system to model the more complicated real-world systems. At the heart of this simplified system is the use of well defined surfaces, typically in the fonn of oriented single crystals. A thorough description of these surfaces should include composition, electronic structure and geometric structure measurements, as well as an evaluation of reactivity towards different adsorbates. Furthemiore, the system should be constructed such that it can be made increasingly more complex to more closely mimic macroscopic systems. However, relating surface science results to the corresponding real-world problems often proves to be a stumbling block because of the sheer complexity of these real-world systems. 

In addition to the many applications of SERS, Raman spectroscopy is, in general, a usefiil analytical tool having many applications in surface science. One interesting example is that of carbon surfaces which do not support SERS. Raman spectroscopy of carbon surfaces provides insight into two important aspects. First, Raman spectral features correlate with the electrochemical reactivity of carbon surfaces this allows one to study surface oxidation [155]. Second, Raman spectroscopy can probe species at carbon surfaces which may account for the highly variable behaviour of carbon materials [155]. Another application to surfaces is the use... 

Detailed and shorter39 45 reviews of the electrochemical promotion literature prior to 1996 have been published, mainly addressed either to the catalytic or to the electrochemical community. Earlier applications of solid electrolytes in catalysis, including solid electrolyte potentiometry and electrocatalysis have been reviewed previously. The present book is the first on the electrochemical activation of catalytic reactions and is addressed both to the electrochemical and catalytic communities. We stress both the electrochemical and catalytic aspects of electrochemical promotion and hope that the text will be found useful and easy to follow by all readers, including those not frequently using electrochemical, catalytic and surface science methodology and terminology. 

The reader already familiar with some aspects of electrochemical promotion may want to jump directly to Chapters 4 and 5 which are the heart of this book. Chapter 4 epitomizes the phenomenology of NEMCA, Chapter 5 discusses its origin on the basis of a plethora of surface science and electrochemical techniques including ab initio quantum mechanical calculations. In Chapter 6 rigorous rules and a rigorous model are introduced for the first time both for electrochemical and for classical promotion. The kinetic model, which provides an excellent qualitative fit to the promotional rules and to the electrochemical and classical promotion data, is based on a simple concept Electrochemical and classical promotion is catalysis in presence of a controllable double layer. 

Previous surface science studies showed that Rh is essential for NOx removal over TWC because NO dissociates more readily on metallic Rh than on Pt and Pd sites [26-28]. Nevertheless, the efficiency of Rh to selectively transform NO into N2 is restricted below the light-off temperature with a predominant formation of N20. Future practical developments are closely related to a better understanding of the formation and on the transformation of N20 over noble metals during the cold start engine. Such an aspect is still challenging over TWC and particularly under lean conditions since the extent in NO conversion is usually significantly lowered. 

In accord with the fact that XPS has become a standard surface science technique but has not been appreciated adequately in electrochemistry, it is the scope of this review chapter to bring XPS nearer to those who work on electrochemical problems and convince electrochemists to use XPS as a complementary technique. It is not the intention to treat fundamental physical and experimental aspects of photoelectron spectroscopies in detail. There are several review articles in the literature treating the basics and new developments in an extensive and competent way [9,13], In this article basic aspects are only addressed in so far as they are necessary to understand and... 

Emersion involves fundamental aspects of condensed matter surface science and electrochemistry, and its consideration offers new insight into these fundamentals. For example, when a new solid or liquid surface is made the atcms or molecules may rearrange at the surface to form a surface dipole layer. This certainly happens... 

Most readers may not appreciate the impact of electrochemistry and/or electrochemical deposition techniques in medicine. In this chapter we discuss these topics as they relate to medical devices. Emphasis is placed on the often overlooked materials science and surface chemistry aspects of medical devices rather than on the topics, described extensively in the literature, of electrochemical sensors in medical apphca-tions. This chapter is intended to provide the reader with a view of the role in medical devices of electrochemistry in general and electrochemical deposition in particular. It is also intended that the reader gain an appreciation of the future potential role of electrochemistry in devices, particularly in the creation of biomimetic (i.e., biology mimicking) medical devices. 

J.R. Rostrup-Nielsen, T.S. Christensen and I. Dybkjaer, in Studies in Surface Science and Catalysis (Recent Advances in Basic and Applied Aspects of Industrial Catalysis, ed. T.S.R.P. Rao and G.M. Dhar, Elsevier Science, 1998, vol. 113, pp. 81-95. 

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