Electron transfer at interfaces

It is hoped that this book will not only be useful to those who wish to work with modem electrochemical ideas in chemistry, physics, biology, materials science, etc., but also to those who wish to begin research on electron transfer at interfaces and associated topics. 

The n-p Junction. Before beginning a discussion of electron transfer at interfaces between H-type semiconductor/solution interlaces, it is helpful to describe something of the theory of the famous n-p junction. This is not a part of electrode-process chemistry (which deals with electron-transfer reactions between electronically and ionically conducting phases), but it is the basis of so much modem technology (e.g., the transistor in computers) that an elementary version of events at the junction should be understood. Further, knowing about the n-p junction makes it easier to understand electrochemical interfaces involving semiconductors. 

It has been pointed out that cytochrome c with its MW of 12,500 is enormous in size compared with the usual entities undergoing electron transfer at interfaces, which have molecular weights of about 100. However, Armstrong et al. (1996) took... 

Ultralast Proton-Coupled Electron Transfer at Interfaces... 

The recent discoveries of superconductivity in materials lacking rare earth elements (1-S) have added new excitement to the already active field of high temperature superconductivity. Studies of heterogeneous electron transfers at interfaces between these... 

An attempt will be made in the following pages to outline the subject of electron transfer at interfaces, on the assumption that the reader is a person familiar with general physical chemistry who has not as yet studied electrochemical kinetics. 

It has been stated that electrochemistry itself is divided into two branches, ionics (the physical chemistry of ions in solution) and electrodics (electron transfer at interfaces). In this article we intend to give a summary of central aspects of electron transfer at interfaces which will be helpful to biophysicists and biochemists who want to know something about the electrical properties of biological situations. 

When one considers electron transfer at interfaces, one has to realize that there is always two-way traffic at any interface. In the one the electrons leave the electrode (or electronic conductor) to reach some entity in solution. In the other the reverse occurs the electrons leave some entity in solution to reach the electronic conductor (Figure 5). 

A large number of disciplines are involved in these studies, not only physics and chemistry, materials science and biology, but also particularly surface science studies and the studies of electron transfer at interfaces with the surrounding ionically conducting phase, i.e., the surface electrochemical phenomena (8). 

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