La₂O₃ nanorods anchoring metal-organic framework derivates for super broadband microwave absorption

Broadband microwave absorption materials have always been the goal of continuous pursuit. Hierarchical interfacial structure and impedance matching design are one of the effective strategies for enhancing broadband microwave absorption (MA) performance. However, the delicate hierarchical interfacial engineering design of magnetic-dielectric structures remains an ongoing challenge. In this work, the novel La(OH)₃ nanorods have been synthesized successfully, and the La(OH)₃ nanorods anchored on the surface of the metal–organic framework (ZIF-67) randomly to form a controllable impedance and hierarchical ZIF-67@La(OH)₃ precursor. After a harsh high-temperature pyrolysis procedure, the La₂O₃ nanorods distribute on the surface of the Co/C polyhedral. The LaCoC-700 nanoparticles demonstrate superior MA performance because of the suitable impedance matching. The minimum reflection loss of the LaCoC-700 value reaches up to −63.0 dB at 3.94 mm, and the effective absorption bandwidth covers 8.56 GHz (9.44–18 GHz) at a thickness of 3.37 mm. Notably, introducing the La₂O₃ nanorods can enhance the interface effect and impedance matching. With the synchronous loss process, the dielectric carbon and magnetic cobalt core can attenuate microwave effectively. This work provides a high and low dielectric loss combination strategy for designing broadband microwave absorbers.