A Review of Recent Advancements in Materials that Absorb Microwave Radiation and Are Derived from Complicated Substances

Abstract

Materials that absorb microwaves are widely used in both the military and the civilian world. Moreover, their importance has increased due to their ability to reduce electromagnetic pollution. High porosity, low density, a wide conjugated backbone, a narrow energy band gap, suitable conductivity and relaxation losses, and a significant specific surface area are all necessary for the ideal conjugated organic polymer for microwave absorption. The types of conductive polymers used as materials that absorb microwaves and their composites to increase their effectiveness are described in this review. Additionally, the structural properties of pure carbon-based microwave-absorbing materials and other conjugated structures with heteroatoms in their chains are analyzed, along with current developments in synthetic techniques. The main mechanisms by which conductive polymers and their composites absorb microwaves are examined, along with particular techniques for modifying these features, such as metamaterial and quasi-antenna qualities. This review offers new possibilities for tailoring conjugated polymers based on their primary mechanisms and clarifies the design of low-density, high-performance microwave-absorbing devices.