MOFs-derived Co-C@C hollow composites with high-performance electromagnetic wave absorption

The composite composed of carbon materials and magnetic particles with the hollow structure is a promising electromagnetic wave absorption material. Herein, we synthesized Z67, Z67-8 and Z67-8@C derived from metal-organic frameworks (M0Fs) by a facile preparation method, and systematically investigated their electromagnetic wave absorption performances respectively. The results show that hollow structured Co-C@C (Z67-8@C) has the best performance. As-prepared Co-C@C achieves a maximum RL of -58.1 dB at 11.52 GHz with an effective absorbing bandwidth (RL less than -10 dB) of 4.56 GHz (9.36-13.92 GHz) when the thickness is only 2.5 mm. Subsequent research verified that such excellent microwave absorption performance of Co-C@C was benefited from the favorable impedance matching. And the cavity inside the material can enhance the absorption performance by multiple scattering and refraction of electromagnetic waves. It is believed that the unique magnetic hollow structure Co-C@C composite material has the potential as a highly efficient microwave absorption material. (C) 2020 Elsevier B.V. All rights reserved.

Automated summary

The study found that the hollow structured Co-C@C shows the best performance in electromagnetic wave absorption, with the potential to become a highly efficient microwave absorption material. The material achieves maximum reflection loss at 11.52 GHz with a thickness of only 2.5 mm. The cavity inside the material enhances absorption performance.