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VO 2 (D) precursor with multi-step petaloid lamination structure was prepared by hydrothermal method, and then VO 2 (M) sample maintaining similar morphology and geometry with that of as prepared VO 2 (D) was obtained by subsequent annealing. The XRD Pattern of VO 2 (D) precursor and annealed samples at different temperature confirms the formation of required crystalline phases and exposes the presence of other intermediate phases. Surface morphology has been analyzed by SEM characterization, which reveals the variation in petaloid microstructure of the annealed samples at different temperatures. The reflection loss measurement results show that multi-step petaloid laminated structure VO 2 (M) sample has excellent microwave absorption performance. The sample annealed at 570 °C has the minimum reflection loss value of −37.99 dB at 3.5 mm, and the effective absorption bandwidth (RL < −10 dB) is up to 4.01 GHz at 1.3 mm. Detailed study shows that the excellent microwave absorption performance of the sample results from the combination of its geometry shape/surface polarization, induced loss and resistance loss. In addition, the curvature of the boundary of the laminated structure also affect the microwave absorption performance of the absorber. The discovery of this work effectively broadens the application of VO 2 (M) and provides a new idea for the design of new absorbing materials with tailored particle morphology. [ABSTRACT FROM AUTHOR]

As important functional materials for absorbing and attenuating incident electromagnetic waves, microwave absorption (MA) materials have found a wide range of applications in civil and military fields. In addition to the study of the compositions, the structural design of the MA materials is also a research hotspot in the field. Among the various structures, the one-dimensional (1D) structure has drawn wide attention because of the unique shape anisotropy and spatial confinement effect. Electrospinning technology has become one of the main ways to prepare continuous 1D micro-nano fibers due to the advantages of many types of spinnable materials, low spinning cost, and high controllability of process parameters. This review involves an introduction and a classification of the research progresses achieved in electrospinning technology concerning MA nanofibers from the perspective of compositions, as well as the list of their minimum reflection loss (RL min) and effective absorption bandwidth (EAB). [ABSTRACT FROM AUTHOR]