Construction of MOF-Derived Co/C shell on carbon fiber surface to enhance multi-polarization effect towards efficient broadband electromagnetic wave absorption

As a typical fascinating microstructure, the core-shell structure provides abundant possibility for material design in various fields including nano-engineering. In addition, the popular MOF derivatives have been widely explored and recognized as the most potential candidates for functional materials, especially in the field of microwave absorption (MA). Combined with the advantages of their structure and function, it is expected to maximize the synergistic effect and achieve amazing MA performance. In this paper, a series of core-shell [email protected]/Co composites were assembled by using lightweight and conductive CF as the core and cubic ZIF-67-derived C/Co with controllable structure and adjustable graphitization as the shell. The intrinsic relationships between shell structure, component content, graphitization degree, electromagnetic parameters and various microwave loss behaviors are analyzed. After properly adjusting the degree of graphitization on the basis of derivation of various C/Co shells, A3-600 with obvious multi-polarization effect were obtained. A3-600 achieves an effective absorption bandwidth of 6.25 GHz at 1.71 mm and the best reflection loss of −71.95 dB at 1.78 mm. This dual strategy of shell evolution design and graphitization control has been proved to be an effective method to coordinate electromagnetic matching and construct multi-polarization effect to enhance the performance of MA.