Metal-organic framework-derived carbon nanotubes for broadband electromagnetic wave absorption

Abstract

The widespread use of communication devices has exacerbated the deterioration of the electromagnetic environment, and thus there is an urgent need to develop more efficient electromagnetic wave (EMW) absorbing materials. Metal-organic frameworks are highly prized for their unique structures and excellent electrical conductivity. Here, in order to break the single way of designing MOF composites and compensate for its lack of magnetic loss capability, an attempt was made to prepare composites with magnetic Co/carbon nanotube (CNT) modification for EMW absorption. The carbon nanotube-encapsulated cobalt metal particles anchored in the matrix enable the composite to enhance electromagnetic wave absorption. Notably, the Co@CNTs/PC composite exhibits excellent EMW absorption performance. A minimum reflection loss of −56.23 dB and a maximum effective absorption bandwidth of 7.36 GHz were obtained at 2.3 mm thickness, respectively. In addition to this, the possible mechanisms involved in EMW uptake are elucidated in detail. These results demonstrate an environmentally friendly and simple strategy for the preparation of MOF substrate-based EMW absorbers.