Filter-paper-derived CF/M/C (M = Co, Ni, or Fe/Fe3O4) 2D interlinked frameworks toward ultrawide absorption bands, high thermal conductivity, and excellent electrical insulation

Reasonable design of protective multifunctional materials is highly required for the safety protection of devices/personnel from electromagnetic radiation and heat damage in the 5G/6G era. Herein, a simple soaking-annealing route was adopted to carbonize filter paper into 2D interlinked carbon fiber frameworks inlaid with magnetic nanoparticles, and the products were referred to as CF/M/C 2DIFs (M = Co, Ni, or Fe/Fe3O4). The concentration and type of metal ions as well as the annealing temperature of the CF/M/C 2DIFs were controlled to precisely modulate their composition, porosity, and defects. Results show that the CF/Co/C 2DIFs produced under Ta = 600 °C and [Co2+] = 0.45 mol/L exhibit high thermal conductivity (2.931 ∼ 3.167 W/m·K) at small loads (10 ∼ 30 wt%) owing to not merely the presence of 2D interlinked path for electron/phonon heat co-transfer but the reasonable control of interface/defects for weakening phonon/electron defect/interface scattering. Also, the CF/Co/C 2DIFs can attenuate microwaves over a broad frequency range via dielectric/magnetic dual loss and 2DIFs, which boosts their loss ability and matching performance. The excellent performance in both heat dissipation and EM wave absorption proves that the CF/M/C 2DIFs can be a promising candidate for next-generation electronic packaging materials in heat management, military, and aerospace fields.