Flexible carbon fibres with magnetic ZIF-67 as a core layer and in situ grown NiMn-LDH nanosheets as a shell layer for microwave absorption†

Abstract

Fabrication of high-performance microwave absorbers by assembling multi-dimensional nanocomponents into core–shell electromagnetic structures has been shown to be a new manufacturing strategy. In this work, a novel core–shell carbon-fibres@ZIF-67@NiMn-layered double hydroxide (NiMn-LDH) film with excellent electromagnetic wave absorption was obtained by electrospinning ZIF-67 inside carbon fibres and subsequent solvothermal process with NiMn-LDH. With the synergistic effects of Co particles in ZIF-67 increasing magnetic loss, the appropriate proportion of the carbon fibres as a carbon source improves dielectric loss and provides a carrier for NiMn-LDH. Furthermore, NiMn-LDH at the outer shell improves impendence matching. Co/carbon fibres@NiMn-LDH (Co/CF@NiMn-LDH) was composited at a thickness of 2.8 mm with minimum reflection loss (R of −53 dB), and it also has good flexibility. The EAB of the obtained CF@NiMn-LDH composite reaches 6.7 GHz. This work provides a reference for the application of flexible carbon matrix composites in the electromagnetic wave absorption field.