Abstract: Research on the electromagnetic interference (EMI) shielding properties of metal-organic frameworks (MOFs) has primarily focused on their derivatives, with limited studies on the EMI shielding mechanism of pure MOFs. Herein, by regulating the types of organic ligands, a series of conductive MOFs (c-MOFs) was constructed, and their EMI shielding effectiveness (SE) was investigated using mechanical compression molding. The c-MOFs sheets exhibit excellent EMI absorption coefficient (A). To explore the mechanism of the heterogeneous structure and EMI shielding mechanism of c-MOFs, c-MOFs were integrated with carbonized wood film (CWF) to construct CWF/c-MOF composites. The flower-like CWF/Ni-HITP (72 S cm^-1) with the larger specific surface area exhibits an outstanding specific EMI shielding efficiency (SSE/t) of 13,901.6 dB cm² g^-1 and achieves an EMI SE of 90 dB at a thickness of 495 µm. Notably, this composite maintains exceptional EMI SE across a broad frequency range (2.6-40 GHz). The c-MOF crystals enhance electromagnetic wave attenuation through multiple scattering and interfacial polarization, while their magnetic metals and π/metal bonds facilitate electron migration, enabling efficient conversion of electromagnetic energy into thermal energy. Additionally, the well-structured layered conductive network of the CWF/c-MOF composite ensures excellent electrothermal performance and thermal stability.

Key words: Electromagnetic interference shielding, Conductive metal-organic frameworks, Carbonized wood film, Broadband