Graphene-based electromagnetic functional materials

Two-dimensional nanomaterials possess excellent electrical, thermal and mechanical properties, exhibiting great potential in the electromagnetic field. Among them, graphene has a large specific surface area and a high carrier concentration, which is the focus of contemporary technology. Herein, the electromagnetic response mechanism, wave absorption and shielding properties of graphene-based electromagnetic functional materials are demonstrated systematically. In the electromagnetic frequency band (2~18 GHz) investigated, electromagnetic losses include conduction loss, multiple relaxation, magnetic resonance and magnetic eddy current generally. Here, the physical formation mechanism and response characteristics of these four electromagnetic loss behaviors are introduced in detail, and the sources of electromagnetic loss of different graphene-based electromagnetic functional materials are summarized. The strategies for designing high-performance electromagnetic functional materials are also proposed. Subsequently, the application standards of high performance electromagnetic functional materials are presented. The response laws of microwave absorption and electromagnetic shielding are put forward. Two methods to improve the electromagnetic response performance are also proposed. For the electromagnetic functional material performances, the latest research progress of graphene-based electromagnetic functional materials in microwave absorption and electromagnetic shielding is introduced. The single-phase and heterogeneous graphene materials, high temperature dielectric properties and electromagnetic responses are covered. In addition, the key problems in the current development of graphene-based electromagnetic functional materials are systematically analyzed, and the research and development directions in the future are prospected. © 2020, Chongqing Wujiu Periodicals Press. All rights reserved.