Construction of hollow and porous carbon Fiber/CoFe composites derived from strawberry petiole for enhanced microwave absorption

Biomass-derived materials have emerged as lightweight and high-efficiency carbon-based microwave absorber for their huge availability and multifarious microstructure. Herein, we synthesize a strawberry petiole derived carbon fiber (SCF) /magnetic CoFe composites (SCF/CoFe) via solvothermal reaction and calcination treatment. CoFe particles are densely and uniformly distributed on the surface of the uniform hollow and porous SCF. After adjusting the calcination temperature, SCF/CoFe sample with filler content of 15 wt% obtains a minimum reflection loss of -40.4 dB and a wide effective absorption bandwidth of 3.5 GHz at a thin thickness of only 2.0 mm. The hollow and porous structure and synergistic effect between conductive SCF and magnetic CoFe simultaneously contribute to the enhanced impedance matching and attenuation ability, which together result in the remarkable microwave absorption properties.