Metal organic framework (ZIF-67)-derived hollow CoS₂/N-doped carbon nanotube composites for extraordinary electromagnetic wave absorption

The hierarchical hollow framework involving interconnected highly conductive N-doped carbon nanotube networks and CoS₂ particles were successfully prepared by metal-organic framework (MOF) derived method. After the two pyrolysis process in the atmosphere of reducing gas and inert gases, numerous carbon nanotubes interlaced on the surface of framework and CoS₂ nanoparticles also attached on the surface. The electromagnetic parameters of CoS₂/NCNTs composites can be well controlled by regulating the loadings of sample in sample-paraffin mixture. The results demonstrate that CoS₂/NCNTs with 50% loadings show superior electromagnetic wave absorption properties in the wide frequency range, almost covering the whole X bands (8–12 GHz) only with a relative thin thickness of 1.6 mm. Hierarchical hollow structure and better impedance matching performance between N-doped carbon nanocube and CoS₂ nanoparticles contribute to the enhancement of microwave absorption ability. Our work confirms that hollow framework CoS₂/NCNTs composites can provide a novel idea for designing high-absorbability microwave absorbers.