Synergistic Polarization Relaxation in Multi‐Level Hybridization and Preferred Orientation Strategies for Electromagnetic Wave Absorption

ABSTRACT Achieving precise control over the electromagnetic response of materials across multiple length scales from atomic to mesoscopic via multi‐level hybridization and preferred orientation strategies remains a central challenge in the development of high‐performance electromagnetic wave (EMW) absorbers. This work successfully prepared a CoSe ₂ /Ni ₃ Se ₂ /CeSe _1.9 /CNFs (CNCS) composite with a multi‐level hybrid structure via a multi‐step hydrothermal‐selenization method. The core innovation lies in the synergistic application of “Multi‐level Hybridization” and “Preferred Orientation” strategies, enabling precise regulation of the material ’ s structure and composition across atomic, molecular, and mesoscopic scales, thereby constructing an efficient multi‐scale collaborative loss network. Consequently, the obtained material exhibits an exceptional minimum reflection loss (RL _min ) of −62.5 dB at a matching thickness of merely 2.9 mm, along with an effective absorption bandwidth (EAB) of 8.3 GHz. This study not only proposes a novel material design paradigm utilizing cross‐scale structural engineering to synergistically regulate multiple loss mechanisms but also provides significant theoretical guidance and design principles for developing next‐generation high‐performance electromagnetic functional materials.