Development of wrinkled reduced graphene oxide wrapped polymer-derived carbon microspheres as viable microwave absorbents via a charge-driven self-assembly strategy.

It is widely recognized that designing a special micro/nanostructure of microwave absorption materials for enhancing interface polarization benefits dielectric loss capability. In this work, a facile charge-driven self-assembly strategy is reported to prepare wrinkled reduced graphene oxide wrapped polymer-derived carbon (CS@rGO) microspheres. Noticeably, the unique three-dimensional (3D) multi-interface structure imparts CS@rGO microspheres with promoted microwave absorption capability. Adjusting the charge-driven self-assembly cycle times, the dielectric properties and impedance matching characteristics of the CS@rGO microspheres can be optimized. The minimum reflection loss (RLmin) of the sample can reach up to -55.24 dB at 13.75 GHz and the effective absorption bandwidth (RL ≤ -10 dB) is 4.30 GHz (11.55-15.85 GHz) at only a thickness of 1.85 mm. This research provides a pathway to explore the high-performance microwave absorber through the construction of the unique 3D multi-interface structure.