Dielectric and Magnetic Loss Behavior of Nanooxides

The need for microwave absorbers and radar-absorbing materials is ever growing in military applications as well as in civilian applications. Whatever the application for which the absorber is intended, weight reduction and optimization of the operating bandwidth are two important issues. A composite absorber that uses nanooxide particles in combination with a polymer matrix offers a large flexibility for design and properties control, as the composite can be tuned and optimized via changes in both the nanooxide inclusions (Ni/OMC, γ-Fe₂O₃@C, C@Ni-NiO, iron oxide, and ZnO) and the embedding matrix (paraffin and epoxy resin). This chapter offers a perspective on the experimental efforts toward the development of microwave absorbers composed of nanooxide inclusions in a polymer matrix. The absorption properties of such composites can be tailored through changes in geometry, composition, morphology, and volume fraction of the filler particles. Polymer composites filled with nanooxide particles provide a versatile system for probing at the nanoscale physical properties of fundamental interest and of relevance to a wide range of potential applications.