Enhanced electromagnetic interference shielding of carbon fiber/cement composites by adding ferroferric oxide nanoparticles

Ferroferric oxide (Fe3O4) nanoparticles were introduced into carbon fiber (CF)/cement composites to enhance the electromagnetic interference (EMI) shielding effectiveness (SE) in X-band (8.2-12.4 GHz). The spherical Fe3O4 nanoparticles were synthesized through solvothermal method, whose average diameter was about 30-50 nm. It was observed that incorporation of Fe3O4 nanoparticles (5 wt%) along with 0.4 wt% CF in the cement matrix led to a shielding effectiveness of 29.8 dB, which had 34.4% increase than that of CF/cement composite. The excellent EMI shielding property was attributed to the synergistic effect between CF and Fe3O4 nanoparticles. SEM revealed the homogeneous dispersion of Fe3O4 and CF in the cement matrix. The CF/Fe3O4/cement composite is believed to be a promising material for high EMI shielding.