Electronic materials chemistry

During the past two decades the science and engineering of electronic materials has become more and more intertwined with chemistry. Chemistry driven by the needs and opportunities of modem materials has lately come to be called materials chemistry. In this paper I would like to focus on electronic materials not only because of personal familiarity but also because they epitomize the interplay between chemistry and materials. From my experience, I would assert that the most important attributes of electronic materials chemistry are ... 

The most important determinant of problem choice in electronic materials chemistry is "are the properties or the process likely to fulfill a device or systems need". This consideration leads to a focus on synthesizing solids, understanding their properties in as fundamental a way as possible, growing crystals to enable understanding and permit devices and understanding the physical chemistry of the processes used so as to permit cost, yield and reliability improvement. 

Figure 2.56. Types of solid oxide fuel cell (SOFC) designs. Reproduced with periuission from Electronic Materials Chemistry, Bernhard Pogge, H. ed., Marcel Dekker New York. Copyright 1996 Taylor ...

Pogge, H. B. Electronic Materials Chemistry, Marcel-Dekker New York, 1996. 

Silver has little tendency to formally lose more than one electron its chemistry is therefore almost entirely restricted to the + 1 oxidation state. Silver itself is resistant to chemical attack, though aqueous cyanide ion slowly attacks it, as does sulphur or a sulphide (to give black Ag S). hence the tarnishing of silver by the atmosphere or other sulphur-containing materials. It dissolves in concentrated nitric acid to give a solution of silver(I) nitrate. AgNOj. 

Nobel-laureate Richard Feynman once said that the principles of physics do not preclude the possibility of maneuvering things atom by atom (260). Recent developments in the fields of physics, chemistry, and biology (briefly described in the previous sections) bear those words out. The invention and development of scanning probe microscopy has enabled the isolation and manipulation of individual atoms and molecules. Research in protein and nucleic acid stmcture have given rise to powerful tools in the estabUshment of rational synthetic protocols for the production of new medicinal dmgs, sensing elements, catalysts, and electronic materials. 

This article has been focussing on poly(phenylene)s with 1,4-(pnra-)phenylene units since these polymers play a key role in the synthesis-driven search for electronic materials. From this article it has become clear that poly(phenylene) chemistry has not restricted its attention to linear (1D-) structures, but has more recently developed into 2D- and 3D-structures as well, the latter serving as functional shape-persistent nanoparticlcs. 

The chemistry and physics of dendritic compounds started a decade ago [1-5]. Today, this science of uniquely shaped molecules, namely, dendrite-shaped molecules, is one of the most exciting topics of contemporary interdisciphnary research. The dendrimers and their related molecules have been investigated widely not only from the viewpoints of synthetic, physical, and material chemistries but also from that of mathematics. Accompanying the development of the science in this decade, research interest has shifted from the mere challenge of preparing molecules with unique shapes, via their excited state chemistries involving inter- and/or intramolecular photo-induced electron and/or energy transfer, to the nanoscience. 

For many years, research efforts in materials chemistry have focused on the development of new methods for materials synthesis. Traditional areas of interest have included the synthesis of catalytic, electronic, and refractory materials via aqueous methods (sol-gel and impregnation) and high-temperature reactions [1-3]. More recent strategies have focused on the synthesis of materials with tailored properties and structures, including well-defined pores, homogeneously distributed elements, isolated catalytic sites, comphcated stoichiometries, inorganic/organic hybrids, and nanoparticles [4-13]. A feature... 

A major contribution from chemistry and chemical engineering has been the development of materials with important military applications. Chemists and chemical engineers, working with experts from areas such as electronics, materials science, and physics, have contributed to such developments as new explosives and propellants, reactive armor (a complex material with an explosive layer that can reduce the penetration of an incoming projectile), and stealth materials that reduce the detectability of aircraft by radar. 

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