Trace iron-induced electron delocalization metallization on the BN surface for hyper integrated C-band wideband absorber

Hyperintegration, (thermal conduction, electromagnetic compatibility etc.) is currently an inevitable trend for portable electronic devices. Boron nitride (BN), with its excellent thermal conductivity and hydrophobicity, emerges as one of the most promising materials. However, its extremely low dielectric parameters and electrical insulation limit its electromagnetic absorption performance. Regulating intrinsic electron spin states can effectively modulate the dielectric properties of high-symmetry structures like BN, yet related studies are scarce. An electron delocalization metallization strategy induced by trace iron doping, utilizing a trace iron-doped zinc metal-organic framework (Zn-MOF) precursor followed by chemical vapor deposition (CVD) carbonization, is proposed. A 3.2 GHz (C-band) wideband absorption is realized. And conductive loss is confirmed to be the dominant loss mechanism for C-band wideband absorption. Full-coverage X-band (3.5 mm) and Ku-band (2.5 mm) electromagnetic absorption is also achieved. Provides a novel framework for BN-based thermally conductive/EMA composite fillers. It lays the theoretical and experimental foundation for the development of lightweight composite materials with both thermal conductivity and wave-absorption dual functions, and has important practical significance for promoting the miniaturization and high reliability of portable electronic devices.