Highly Selective Nano‐Interface Engineering in Multishelled Nanocubes for Enhanced Broadband Electromagnetic Attenuation

Abstract Within the nanoscale, methodically reconfiguring interface charges, and leveraging this newly structured interface to modify the energy‐momentum dynamics of heterojunction energy bands, hold profound implications for microwave electronics because of the intensified interaction between external microwaves and interfaces of materials. Mastering the orderly reconstruction of interface charges, contingent upon precise control over composition, orientation, and electronic structure remains a challenge at this scale. Herein, an in situ hierarchical assembly approach is used to successively deposit layers of Cu₂S, C, and MoS₂ on a hollow cubic framework with a thickness of 20 nm. Additionally, by harnessing the quasi‐graphitic characteristics and elevated work function of graphitized carbon in the middle layer, its inherent charge is steered toward both the outer and inner layers, establishing a structured configuration for the crafted Cu₂S@C and C@MoS₂ interfaces. Employing advanced off‐axis electron holography, microwave dielectric measurements, and first‐principle calculations, the dynamic reconstruction of interface charges and the resulting microwave response is ascertained. The synergistic effect revealed that the Cu₂S@C@MoS₂ materials exhibited exceptional microwave absorption, with an effective absorption band covering 7.03 GHz at 2.0 mm thickness. Furthermore, the orderly reconstruction of nano‐interfaces paves the way for research into novel electromagnetic protection materials and their unique electronic behaviors.