Auricularia-shaped MoS₂ nanosheet arrays coated hierarchical multilayer MoS₂/PPy/rGO composites for efficient microwave absorption

The rapid development of electronic technology has exacerbated electromagnetic pollution. It's crucial to develop efficient microwave-absorbing (MA) materials for blocking electromagnetic damage to electronic instruments and human health. However, simple structure MA materials usually have limited microwave absorption capacities and cannot simultaneously meet requirements for lightweight, wide bandwidth, and high loss. Constructing hierarchical structure composites and thereby introducing multiple absorption mechanisms is an effective way to improve the MA performance. In this study, we synthesized an auricularia-shaped MoS₂ nanosheet array coated hierarchical multilayer MoS₂/PPy/rGO (MPG) composite by a facile hydrothermal method. In the preparation process, using PPy to modify the rGO surface plays a key role, which effectively avoids rGO agglomeration and provides substrates for MoS₂ nanosheets to grow on. The thicket of MoS₂ nanosheets creates numerous nanoscale interfaces, promoting interface polarization and improving impedance matching. The multilayer heterogeneous structure facilitates multiple reflections and scattering, further attenuating electromagnetic waves. By optimizing the addition of PPy, the material's microstructure and microwave absorption performance were improved. The MPG-10 sample achieved the best reflection loss of −53.5 dB (2.07 mm thickness) and an effective absorption bandwidth of 5.36 GHz (1.82 mm thickness). This work contributes a new idea for the structural design of graphene-based hierarchical heterogeneous microwave absorption materials.