THERMODYNAMIC AND TRANSPORT-PROPERTIES OF ELECTROCERAMIC OXIDE SYSTEMS

Ceramic oxides are finding a wide range of application as materials for electronic systems in the modern world. They are used as electrodes and electrolytes in fuel cells and oxygen sensors, and as magnetic and dielectric materials in control devices, to mention only a few examples. Because of their nature, the fabrication of components incorporating ceramic oxides is usually carried out at high temperatures. The transport properties and redox properties of the constituent ions in these materials therefore play a significant role in determining the ease of fabrication as well as the scope of application of devices. Examples of the limitations placed on the use of these materials as a result of the chemistry of the systems are summarized for a number of current uses. The possibility of using an assembly of contemporary information to develop new and more useful materials is examined in terms of the oxygen and temperature sensitivity of the desired physical properties of electroceramics. It appears that the field is still open to many new developments, largely because of the wide range of cationic mixtures which can be sustained in the structural and stability properties of these materials.