Organic conductors overview

In this chapter we give a broad overview of the field of organic conductors, discussing in a general way the key issues that distinguish these from the more conventional conductive compounds. In later chapters, each topic is treated in greater detail by experts in these areas. Our effort will be to paint a broader picture and to attempt to show how the study of these systems fits with the rest of condensed-matter physics. 

As discussed in Chapter 1, organic conductors, because of their intrinsic lower dimensionality, can show very diversified thermodynamic behavior [1]. This proved very early to be an unexpected challenge to theorists and experimentalists. New phenomena were explored new theoretical tools and new experimental techniques had to be developed. It is the purpose of this chapter to present an overview of the phenomena and the tools that have occupied the theorists in the 20 years of existence of the field covered by this book. 

The study of organic semiconductors and conductors is highly iaterdisciplinary, involving the fields of chemistry, soHd-state physics, engineering, and biology. This article provides a treatment of the theoretical aspects of organic semiconductors as well as an overview of recent advances ia the field and the uses of these materials based on their conductive and optical properties. 

Another approach was the synthesis of inorganic/organic composite materials to influence the properties of the membrane. An overview on the state of the art of composite perflourinated membranes is given in [15]. Infiltration of a polymer carrier material with various inorganic proton conductors is subject of a patent [16]. For operation at elevated temperature, several materials have been considered, hi an early work, Nafion /Fl3P04 showed better conductivity at temperatures above 100°C compared with blank Nation and also reduced methanol permeabihty [17]. New types of polymers are also under development for better temperature stabihty one of the most advanced examples is the high-temperature material polybenzimidazole, which usually is doped with phosphoric acid [18]. 

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