Preparation of ZnO/Co/C/RGO\nComposites for Enhanced\nMicrowave Absorption

ZnO/Co/C/reduced\ngraphene oxide (RGO) composites are synthesized\nthrough carbonization of ZnCo-MOF-5/GO under an Ar/H<sub>2</sub> flow.\nThe abundant active sites (e.g., functional groups and lattice defects),\ncopious heterointerfaces (among Co, ZnO, C, and RGO), and wrinkled\narchitecture trigger multiple dipole polarization, interface polarization,\nand enhanced conductive loss. By adjusting the content of RGO, the\nelectromagnetic parameters for ZnO/Co/C/RGO composites were effectively\nregulated. The minimum reflection loss (RL<sub>min</sub>) of ZnO/Co/C/RGO-50\ncomposites is −52.72 dB at 1.70 mm, and the EAB is 3.57 GHz.\nFuthermore, CST simulation results further confirm the remarkable\nRCS reduction capacity for ZnO/Co/C/RGO-50 composites. The reduction\nvalue of RCS is 22.84 dB m<sup>2</sup>, and effective absorption can\nreach the entire angle range. The superior microwave absorption property\nfor ZnO/Co/C/RGO composites is benefited from cooperative action of\ndielectric loss (dipole polarization, interface polarization, conductive\nloss) and magnetic loss (natural resonance and exchange resonance).