Magnetic/electric synergy Co@CN/CNTs absorber toward high efficiency electromagnetic waves absorption

Abstract

Metal-organic framework (MOF) has gained widespread attention as promising electromagnetic waves (EMWs) absorbent due to its 3D structure, porosity and easier modification. However, the structural instability and impedance mismatch presented a serious challenge in meeting the ultra-strong and ultra-broad absorption requirement for EMWs. Therefore, a facile strategy has been applied to prepare carbon nanotubes modified nitrogen-doped carbon encapsulated Co (Co@CN/CNTs) composites by regulating the mass ratio of Co-ZIF67 and melamine under high-temperature pyrolysis. The in-situ synthesis of CNTs and doping of nitrogen-atoms optimized the impedance matching of Co@CN/CNTs composites. The 3D heterostructure, porosity, surface defects and conductive network enhanced EMWs absorption ability. The ultra-strong reflection loss (RL) for Co@CN/CNTs-1:1 sample of −112.14 dB was reached with only 1.3 mm match thickness and corresponding ultra-broad effective absorption bandwidth (EAB) was up to 8.2 GHz. This research could be expected to provide a novel scheme for design and preparation of MOFs derived EMWs absorption materials.