Bird-Nest-Like Multi-Interfacial MXene@SiC_NWs@Co/C Hybrids with Enhanced Electromagnetic Wave Absorption

Newly emerged two-dimensional transition metal carbides and/or nitrides (MXenes) have attracted considerable interest in the field of electromagnetic wave absorption, but their excessive conductivity and single loss mechanism limit their applicability. Herein, an MXene decorated with SiC_NWs@Co/C was prepared by in situ growth and carbonization processes, followed by electrostatic self-assembly. The electromagnetic wave absorption performance of MXene@SiC_NWs@Co/C with a bird-nest-like structure could be effectively regulated and optimized by changing the proportion of MXene and SiC_NWs@Co/C. The prepared MXene@SiC_NWs@Co/C hybrid absorbers reveal superior impedance matching, complementary dissipation mechanism, and plentiful heterointerfaces. Profiting from the synergy of abovementioned factors, the resultant MXene@SiC_NWs@Co/C absorber exhibits an optimum reflection loss (RL) value of −76.5 dB at 6.36 GHz under a thickness of 3.9 mm and broad effective absorption bandwidth (EAB, RL ≤ −10 dB) of 6.2 GHz (11.8–18.0 GHz) with a thickness of only 2.0 mm, covering the entire Ku band. This work offers new insights into designing and fabricating highly efficient MXene-based electromagnetic absorbers.