Cold sintering process induces dielectric resonance in Mo-MXene/ReFeOx (Re = Ce, Er, Gd) sintered body for EMW absorption

Dielectric resonance arises from the collective oscillation of local electrons between adjacent, non-contacting particles under an external alternating electric field. Adjusting the spacing between particles to induce a dielectric response is crucial for electromagnetic wave (EMW) absorption capability. This work introduces an innovative cold press sintering (CSP) technique conducive to generating dielectric resonance; this method effectively anchors rare-earth (RE) magnetic nanoparticles onto a two-dimensional (2D) Mo-MXene conductive substrate while allowing for the controllable adjustment of the spacing between nanoparticles. Furthermore, compared to high-temperature sintering, low-temperature CSP mitigates the oxidation of Mo-MXene nanosheets, preserves their high electrical conductivity, and facilitates electron supply to the loaded magnetic nanoparticles. Experimental results and theoretical simulations demonstrate that Mo-MXene/ReFeO x (Re = Ce, Er, Gd) exhibits distinct dielectric resonance characteristics, thereby enabling the modulation of dielectric resonance-type loss in RE magnetic materials. Additionally, Mo-MXene/ReFeO x maintains excellent magnetic stability across various temperatures. This technique demonstrates versatility, as dielectric resonance phenomena, and the resulting superior EMW absorption performance, are observed in Mo-MXene/CeFeO x , Mo-MXene/ErFeO x , and Mo-MXene/GdFeO x sintered bodies, with reflection loss ( R L ) values of -49.69 dB, -33.18 dB, and − 40.13 dB, respectively. Radar cross-section (RCS) simulations indicate that Mo-MXene/ReFeO x sintered bodies inherit practical potential for radar stealth applications. In summary, this work breaks through the traditional paradigm of relaxation loss modulation and offers a novel perspective for the design of dielectric resonance-type EMW absorption materials.