Integration of MCMBs/MWCNTs with Fe3O4 in a flexible and light weight composite paper for promising EMI shielding applications

Insights into advances in portable and flexible electronic devices can be gained from the integration of magnetic nanoparticles with light weight and flexible conductive supports, especially in cases where the thickness of the material is challenging for future electromagnetic interference shielding applications. Here we report the fabrication of flexible shielding materials made up of Fe3O4 nanoparticles incorporated mesocarbon microbeads and multiwalled carbon nanotubes (MCMBs/MWCNTs) composite paper for efficient electromagnetic interference (EMI) shielding in the X-band frequency region (8.2-12.4 GHz). The incorporation of Fe3O4 nanoparticles in the MCMBs/MWCNTs composite paper significantly increases its interfacial polarization and anisotropy energy, which leads to an excellent absorption dominated EMI shielding effectiveness (SE) of -80 dB at 0.5 mm thickness. The composite paper also exhibits improved magnetic properties coupled with enhanced dielectric properties that increase with increasing concentration of Fe3O4 nanoparticles. Our measurements have provided a regime for designing conductive networks with advantages of light weight and flexibility, with promising EMI shielding applications.