Carbon-based EM functional materials and multi-band microwave devices: Current progress and perspectives

Owing to their low electromagnetic pollution, high flexibility, tunability, and environmentally friendly properties, carbon-based EM functional materials are considered to be potential candidates for the designs of next-generation microwave devices. The purpose of this review is to survey and systematize the growing body of literature on carbon-based microwave devices and to help establish better guidelines for future research and development on the subject. So far, research on the application of carbon-based functional materials in microwave device design has been actively carried out. At present, the carbon materials widely used in electronic devices mainly include graphene, carbon nanotubes (CNTs), and MXene. Here, we systematically review the applications of different carbon-based functional materials in metamaterial absorbers, metasurfaces, antennas, and flexible sensors, and also introduce the application of carbon-based composite functional materials. Microwave devices based on the above materials show great promise in areas such as 6G, wireless body area networks, and wearable health monitoring devices. Although microwave devices designed based on some carbon-based functional materials are currently only in the ideal simulation stage, as the production system of new materials matures, it can be assumed that more opportunities for the development of the next generation of microwave devices will be provided. Last but not least, the development of carbon-based EM functional materials in multi-band microwave devices is summarized, and the new tendency is prospected.