Rail-like heterostructured porous carbon composites derived from vanadium metal-organic framework/butterfly wings for enhanced microwave absorption

Over the recent years, carbon materials derived from biomass have gained extensive interest owing to their structural diversity and high porosity. In this work, butterfly wings (BWs) with concave-cavity-array structure and vanadium-containing metal-organic framework (V-MOF) are selected as precursors, and a rail-like heterostructure composed of V 2 O 3 @C/BWs derived carbon (BWC) composite is constructed by a facile solvothermal reaction and one-step carbonization procedure. The unique concave-cavity-array structure of BWs is conducive to multiple reflections and scattering of electromagnetic waves (EMWs). Moreover, the V-MOF derived V 2 O 3 @C microspheres are uniformly dispersed on the surface and concave cavities of BWC, which generates abundant heterogeneous interfaces and boosts the interfacial polarization. The results show that the minimum reflection loss of V 2 O 3 @C/BWC composites reaches −59.3 dB, and the effective absorption bandwidth is up to 6.56 GHz, which covers the entire Ku-band. In addition, under the incidence angle of 15°, the maximum radar cross section reduction value of V 2 O 3 @C/BWC materials is found to be 43 dB m 2 . Overall, this work provides a new approach to develop carbon-based EMW absorbers with strong and ultra-wideband absorption.