A kind of glucose‐derived carbon‐rich silicon oxycarbide (glucose‐SiOC) nanocomposite with excellent electromagnetic wave absorbing performance is obtained via solvothermal method, and then pyrolyzed at high temperature (1300°C and 1400°C) under argon atmosphere. The structural evolutions and the electromagnetic wave absorbing capabilities of the nanocomposites have been systematically investigated. The resultant 3 mol/L glucose‐SiOC ceramic exhibits a heterostructure, in which nanosized glucose‐derived carbon and SiC particles decorate on amorphous SiOC network. Benefitting from the nanosized carbon, SiC particles and the heterostructure attributes, the 3 mol/L glucose‐SiOC ceramic displays a strong electromagnetic wave‐absorbing property. The minimum reflection coefficient of the 3 mol/L glucose‐SiOC ceramic pyrolyzed at 1400°C reaches −27.6 dB at 13.8 GHz. The widest effective absorption bandwidth attains 3.5 GHz in Kμ‐band. This work opens up a novel and simple route to fabricate polymer‐derived ceramics with excellent electromagnetic wave‐absorbing performance.

Nowadays, metal oxide-based electromagnetic wave absorbing materials have aroused widely attentions in the application of telecommunication and electronics due to their selectable mechanical and outstanding dielectric properties. Herein, the binary ZnO/NiCo2O4 nanoparticles were successfully synthesized via hydrothermal reaction and the electromagnetic wave absorption properties of the composites were investigated in detail. As a result, benefiting from the dielectric loss, the as-obtained ZnO/NiCo2O4-7 samples possessed a minimum reflection loss value of −33.49 dB at 18.0 GHz with the thickness of 4.99 mm. This work indicates that ZnO/NiCo2O4 composites have the promising candidate applications in electromagnetic wave absorption materials in the future.

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Herein, the SiC‐coated carbon fiber decorated with SiC nanowire (SiCnw/CF) composites are successfully prepared by one‐step chemical vapor infiltration (CVI) process. Microstructures, the formation mechanism of SiCnws, thermal stability performance, and electromagnetic wave (EMW) absorption performance of the composites are investigated in detail. In particularly, benefiting the dielectric loss and conductive loss, the SiCnw/CF composites obtained at 1500 °C exhibit superior EMW absorption property with the minimum reflection loss (RL) of −36.5 dB with the effective absorption band of 5.5 GHz at a thickness of 1.88 mm. This work provides a simple way to obtain and design the CF‐based materials with good microwave absorption.

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