Ultra-small Co/CNTs nanohybrid from metal organic framework with highly efficient microwave absorption

The application of composites of carbon matrix and ferromagnetic nanoparticles as electromagnetic wave absorption materials has received extensive attention. In this study, we successful synthesized metal organic framework (MOF) with dodecahedron shape by the decomposition of Co-based precursor of zeolitic imidazolate framework (ZIF -67). And to further improve the absorbing performance, acetylene was introduced to obtain ultra-small Co/CNTs nanohybrids. During CVD process, Co nanoparticles of MOF cracked into Co nanocrystals catalyzing the growth of carbon nanotubes (CNTs). Among three composites of ZIF-67, MOF and Co/CNTs, the Co/CNTs presented the better performance for electromagnetic wave absorption. Particularly, the maximum reflection loss (RL) of Co/CNTs reached −49.16 dB in case of the absorber thickness of 2.5 mm. The excellent absorbing performance is more likely attributed to the novel structure and the double losses of magnetic Co and dielectric CNTs.