Hierarchical Co/CoO/FeO/C nanocomplex derived from Co(OH)2@NH2-MIL-88 to aid highly efficient microwave absorption

Design of microwave absorbents with hierarchical interfacial structures has become an effective method to scatter microwaves. Metal/carbon composites derived from metal–organic frameworks (MOFs) have attracted considerable attention due to their tunable chemical composition and microstructure. We describe the facile synthesis of a Co/CoO/FeO/C nanocomplex employing Co(OH)2 on NH2-MIL-88B as the “sacrificial template” through one-step pyrolysis. The as-prepared flaky-like Co/CoO/FeO/C nanocomplex showed an effective absorption width of 4.7 GHz at 1.86 mm and a minimum reflection loss of −45.5 dB at 2.01 mm. Our study can aid design of a microstructural strategy for preparing high-performance microwave absorbents.