Controllable heterogeneous interfaces and dielectric modulation of biomass-derived nanosheet metal-sulfide complexes for high-performance electromagnetic wave absorption

Constructing new environmentally friendly dielectric coupling models is an effective strategy for designing high-performance wave absorbers. However, biomass carbon materials with high potential energy and a lack of magnetic response mechanism do not fulfill the requirements. In this work, the effects of different pyrolysis temperatures and the introduction of different metal sulfides on the microscopic morphology and dielectric-magnetic properties of the composites were investigated. Among them, K element detected in the biomass effectively modulates the conduction loss. The minimum reflection loss (RLmin) of –62.42 dB at 1.8 mm and the maximum effective absorption bandwidth (EABmax) of –62.42 dB at 1.9 mm were obtained due to the non-uniform interfacial-induced polarization of the metal-sulfide nanosheets and the scattering of the electromagnetic waves (EW) by the “island” microstructures. This study provides a powerful reference for the modification and application of biomass materials.