Synergistic Modulation Ion Regulation and Lattice Distortion Tailoring Built‐In Electric Fields for Electromagnetic Wave Absorption

ABSTRACT Heterogeneous interface engineering is the core strategy for developing advanced microwave absorbing materials. In this study, through precise ion regulation, lattice distortion was induced and polarization loss was enhanced. The ion radius difference of sulfur based anions (S 2− /Se 2− /Te 2− ) was utilized to induce interface reconstruction, forming controllable lattice distortion, which resulted in abundant heterojunctions and high density defect dipoles. Experimental and theoretical analyses reveal that lattice distortion considerably breaks the periodic lattice potential field and collaborates with the interfacial modulation effect of NiCo hollow microspheres to boost charge separation and migration, strengthen polarization relaxation loss, and construct multiple Mott–Schottky heterojunctions with a robust built‐in electric field. Among them, the BNC‐Se2 sample exhibited excellent microwave absorption performance due to the optimal lattice distortion effect and interface synergy: at a thickness of 2.3 mm, the minimum RL min reached −60.8 dB, and the effective absorption bandwidth covered 7.84 GHz. This study achieved precise control over the lattice distortion at the heterojunction through space charge engineering. It clarified the microscopic mechanism by which lattice distortion cooperates to enhance polarization loss, and provided a new paradigm and experimental basis for designing lightweight, thin layer, wide bandwidth high performance microwave absorption materials.