Heterogeneous structure design of Co3InC0.75/In/C derived from dual MOFs with core-shell structure for broad microwave absorption bandwidth

Abstract

Metal-organic frameworks (MOFs) derivatives have attracted widespread attentions as microwave absorption materials because of their high specific surface area, low density, porous structure and easily integration with other materials. Herein, bimetallic carbides (Co3InC0.75) encapsulated into porous carbon skeletons are synthesized by the carbonization of MIL-68 (In)@ZIF-67 (Co) nanorods with core-shell structure as precursor at 800 °C. ZIF-67 (Co) dodecahedron nanoparticles are synthesized on surface of MIL-68 (In) nanorods by an in-situ synthesis at room temperature. Microwave absorption properties and mechanisms of Co3InC0.75/In/C nanocomposites with nanorods are investigated in depth. Co3InC0.75/In/C nanocomposites with nanorods structure can achieve a minimum reflection loss of −29.65 dB at 16.26 GHz under a thickness of 2.0 mm and effective absorption bandwidth of 6.89 GHz (covering X-band of electromagnetic wave) under a thickness of 2.3 mm, which can be attributed to the synergistic coactions of impedance matching, porous structure, a large amount of heterointerfaces and carbon matrix. This study sheds light on that porous carbon encapsulated by bimetallic carbides as high efficiency microwave absorption materials have a potential practical application for addressing electromagnetic radiation and pollution.