Hierarchical structure SiC@CoNi-layered double hydroxide fibers for high performance electromagnetic wave absorption

Abstract

The electromagnetic radiation/interference problem caused by the widespread use of electronic devices increasingly heightens the need for developing excellent electromagnetic wave (EMW) absorption materials. Silicon carbide (SiC) fibers are widely applied in EMW absorption due to their low density, overlapping 3D conductive network and high aspect ratio. However, the low dielectric properties of SiC fibers limit their further application in EMW absorption. Designing heterogeneous interfaces through material composition is of great significance for optimizing the dielectric properties and achieving superior EMW absorption performance. Therefore, hierarchical structure SiC@CoNi-layered double hydroxides (CoNi-LDHs) fibers were designed by constructing heterogeneous interfaces using electrospinning technology and the hydrothermal method. The numerous heterogeneous interfaces formed between petal-like CoNi-LDHs and SiC fibers enhance the dielectric properties of SiC fibers. In addition, the complex permittivity of the SiC@CoNi-LDHs fibers can be effectively regulated by changing the Co²⁺/Ni²⁺ molar ratio. The results show that the reflection loss (RL) of SiC@CoNi-LDHs fibers reaches −50.1 dB and the effective absorption bandwidth (EAB) is 7.0 GHz. The SiC@CoNi-LDHs fibers with tailored heterogeneous interfaces designed in this study provide a valuable approach for designing EMW absorption materials with strong RL and a broad EAB.