Fe3O4/expanded graphite/paraffin nanocomposites for both electromagnetic interference shielding and heat management

A Fe3O4/expanded graphite (EG)/paraffin nanocomposite was successfully developed for electromagnetic interference (EMI) shielding and heat management. The combination of magnetic Fe3O4, non-magnetic EG, and paraffin resulted in an impressive EMI shielding effectiveness (EMI SE) of 67.26 dB with a thickness of 2.2 mm, far surpassing the commercial standard of 20 dB. A peak EMI SE of 89.74 dB was recorded at 10.8 GHz. The nanocomposite also demonstrated enhanced heat management properties, with a latent heat density of 164.7 J g-1, attributed to its dual EG-paraffin heat transfer network. The high phase transition enthalpy allowed the nanocomposite to absorb and retain significant heat, making it suitable for high-power and high-frequency electronic applications. These results highlight the potential of Fe3O4/EG/paraffin nanocomposites for effective EMI shielding and heat management.