Synthesis and shielding properties of PVP-stabilized-AgNPs-based graphene nanohybrid in the Ku band

- Three component nanohybrid of polyvinyl pyrrolidone stabilized silver nanoparticles based graphene sheets (Ag-PVP-CRG) has synthesized via solvent assisted reduction of graphene oxide sheets.
- Average diameter of PVP-stabilized AgNPs onto CRG sheets is ∼15-30 nm.
- Nanohybrid showed excellent electromagnetic shielding properties (SE 58 dB in the Ku band frequency range) at 2 mm thickness which overcome the SE value of graphene oxide (only 10 dB).

PVP-stabilized silver nanoparticles (AgNP)-based graphene nanohybrid (Ag-PVP-CRG) have been synthesized and high performance shields for electromagnetic interference (EMI) in the microwave region have been developed. Morphological characterization of Ag-PVP-CRG nanohybrid by scanning electron microscopy, X-ray diffraction and high resolution transmission electron microscopy revealed PVP-stabilized AgNPs (diameter: 15-30 nm) decorated graphene sheets. The Ag-PVP-CRG nanohybrid showed excellent shielding response in the Ku band frequency region, which is majorly governed by absorption losses. The results show that the total EMI shielding effectiveness (SE) value is 58 dB for Ag-PVP-CRG at 2.0 mm thickness in the Ku-band region, dominated by absorption mechanism, which overpowered the 10 dB value of graphene oxide. The presence of AgNPs on graphene sheets enhances space charge polarization, multiple scattering and effective anisotropy energies of the nanohybrid, resulting in high electromagnetic shielding effectiveness. The dielectric behavior was evaluated to correlate with the EMI shielding mechanism.

Ordering of metal nanoparticles in a carbon nano-structure is requisite to obtain materials with tailored properties.258