Insight of multi-polarization effect by constructing high-entropy spinel ferrite/perovskite @ amorphous carbon for enhancing electromagnetic wave absorption

Microstructure and morphology have been utilized to effectively modulate the electromagnetic wave (EMW) absorption properties of materials, thereby mitigating electromagnetic pollution and enhancing communication quality. However, achieving effective and practical integration of these factors remains a significant challenge. In this study, we investigated novel porous (Co_0.2Mn_0.2Ni_0.2Cu_0.2Zn_0.2)Fe₂O₄/LaMnO₃@C spinel/perovskite dual-core @ amorphous carbon shell nanocomposites. Beyond constructing abundant heterogeneous interfaces and defects, Mn ions in various oxidation states were strategically incorporated to enhance EMW absorption performance. The excellent dielectric loss capability attributed to the typical multi-polarization effect, coupled with the superior magnetic loss ability provided by the high-entropy spinel core, enables the resulting nanocomposites to achieve an impressive bandwidth of 7.88 GHz (10.12–18 GHz) at a thickness of 2.4 mm, covering a wide frequency range almost from X band to Ku band. This study elucidates the substantial positive impact of controllable microstructural design and multi-polarization effect on broadening EMW absorption bandwidth, opening up a novel avenue for the exploration and fabrication of broadband EMW absorbing materials.