Mushroom cap-shaped porous carbon particles with excellent microwave absorption properties

Highlights: • The mushroom cap-shaped porous carbon particles (MRC-C) were successfully fabricated. • Reasonable microstructure design is conducive to improve microwave absorption. • The MRC-C900 displays excellent microwave absorption properties. The mushroom cap-shaped porous carbon particles (MRC-C) were successfully obtained through the etching-pyrolysis of phenolic resin coated silica composites. Based on the systematic characterization and analysis of MRC-C series materials, we found that reasonable structural design can significantly enhance the microwave absorption (MA) performance of materials. In this work, the minimum reflection loss (RL_min) of MRC-C reaches −42.40 dB at 14.86 GHz at a thickness of only 1.6 mm, and the corresponding effective absorption bandwidth (EAB) reaches 4.37 GHz. Such remarkable MA performance is mainly ascribed to well impedance matching and microwave loss capability, which are derived from structural characteristics and strong loss characteristics. In addition, the structure of MRC-C can greatly reduce the density of the material, which is more in line with the requirements of practical applications. We believe that this work can provide important theoretical reference for the construction of ideal high-performance microwave absorbers.