Electromagnetic interference shielding performance by thermally stable magnesium ferrite encapsulated polythiophene composite

摘要

Magnesium ferrite (MgFe_2O_4) nanorods and magnesium ferrite/polythiophene (MgFe_2O_4/PTh) composites have been fabricated by sol-gel and in-situ emulsion polymerization approach to investigate EMI (electromagnetic interference) shielding activity in the X-band region. The encapsulation of MgFe_2O_4 nanorods by conducting PTh decreased the coercivity and improved the conductivity of the composites. The composite with a maximum loading of MgFe_2O_4 nanoparticles (MP-21; MgFe_2O_4∶PTh = 2∶1) displayed superior magnetic moment (23.27 emu/gm) and coercivity (0.023 kOe). In addition, the composite (MP-21) exhibited the highest SE (shielding effectiveness) of - 40.17 dB at 10.29 GHz by 1 mm thick pellet for X-band region (8.2-12.4 GHz). The excellent shielding behavior of the composite is attributed to the synergistic effect of these two moieties resulting in the high dielectric and magnetic loss. Moreover, the porous and rod-like morphology of these composites further induces microwave absorption ability. These results revealed that MgFe_2O_4/PTh composite showed the maximum EMI shielding property, which can find potential application as a lightweight, high-performance EMI shielding material.