Magnetic Properties of Conducting Polymers

Abstract

Modern society is dependent on different devices in which the fundamental behavior is deeply attached to the magnetic and electrical properties of the components used to build them. Until now, the development of new materials guarantees the improvement of the efficiency of these devices. However, new functionalized materials are necessary to the development of the next generation considering not only efficiency, but low environmental impact, durability, and low toxicity. One important concern is material weight and mild synthesis methods. In this sense, since the discovery of conducting polymers, in 1977, there are many and important applications of these materials. These compounds have as special properties the possibility to have their conductivity modulated between 10−6 up to 103 S cm−1. Besides, most of them are redox materials, meaning they can be reversibly changed between the reduced (dielectric) and oxidized states (semiconductor). On the other hand, fundamental aspects of their behavior are still a challenge to researchers of many areas due to the very drastic changes associated with the redox behavior, such as conductivity, spectral absorbance, ionic intercalation, volume change, and more recently, magnetic properties. Specifically, this chapter presents a review about those works which have investigated the magnetic properties, its correlation with synthesis methods and redox behavior as well as the morphological effect. The concern of this chapter is to analyze the different magnetic phases present in conducting polymers, in particularly, antiferromagnetic, ferromagnetic phases observed at room temperature in some of these materials, which open many possibilities for different applications.