Design of mesoscopic metacomposites for electromagnetic wave absorption: enhancing performance and gaining mechanistic insights

The increasing issue of electromagnetic pollution necessitates the development of high-efficiency microwave absorbing materials. Traditional composites present challenges due to temperature sensitivity, complicating impedance matching and loss capabilities across varying temperatures. Rather than concentrating on the micro-scale structures and components typical in traditional design strategies, mesoscopic metacomposites have garnered significant attention due to their capacity to enhance microwave absorption and impedance matching through a discrete distribution of subwavelength-scale functional units in the composites. This review focuses on the applications of mesoscopic metacomposites in improving microwave absorbing performance. The discrete arrangement of subwavelength units improves anti-reflection effects and provides significant intrinsic loss capacity, enabling strong attenuation and effective impedance matching. Additionally, mesoscopic metacomposites facilitate controlled reflection and scattering of electromagnetic waves by carefully designing conductivity, dimensions, and spatial configurations. This presents groundbreaking methods for the further enhancement of microwave absorption efficacy. This review aspires to illuminate the pathway toward the development of thin, lightweight, highly efficient microwave absorbing materials with broadband absorption capabilities.