Enhanced microwave absorption properties in polyaniline and nano-ferrite composite in X-band

Highly conducting polyaniline (PANI) nanocomposite with Mn0.2Ni0.4Zn0.4Fe2O4 ferrite was prepared by mechanical blending. The present work reports the EMI shielding characteristics of the ferrite-Pani nanocomposite with different thickness. The saturation magnetization (Ms) for pure MnNiZn ferrite (52 emu/g) and composite (41 emu/g) was measured by VSM at room temperature. The crystalline size of MnNiZn ferrite was found in the range of 25-30 nm as analyzed by TEM and XRD. The complex permittivity, permeability and shielding effectiveness of the composite for different thicknesses were measured in the 8-12 GHz (X-band) frequency range. The composite of 2.5 mm thickness has shown high shielding effectiveness (49.2 dB) due to absorption (SEA). The high value of SEA suggests that this composite can be used as a promising absorbing material for X-band frequency range. (C) 2010 Elsevier B.V. All rights reserved.