Polyaniline-Coated ZIF-67-Derived Co/C Nanostructures for Efficient Electromagnetic Wave Absorption

Metal–organic frameworks (MOFs) have diverse structures, thus sparking strong research interest in the field of electromagnetic wave (EMW) absorption. In this work, zeolitic imidazolate framework-67 (ZIF-67) was hydrothermally synthesized and thermally annealed to form rhombic dodecahedral Co/C nanocomposites with desirable porous structures. Then, a layer of rod-shaped polyaniline was coated on the surface of the Co/C nanocomposites through in situ polymerization. The effect of the mass ratio of polyaniline to Co/C on the electromagnetic properties of the nanocomposites was studied. The sample Co/C@PANI-2 exhibited an optimal reflection loss of −67.67 dB and an effective absorption bandwidth of 5.02 GHz at a filling ratio of 50%. The rod-like polyaniline coating effectively enhanced the electromagnetic properties and impedance matching of the nanocomposites. This work provides a reference for the composite of MOF-derived nanomaterials and conducting polymers in EMW absorption studies.