Preparation and electromagnetic properties of Polyaniline(polypyrrole)- BaFe ₁₂ O ₁₉ /Ni _0.8 Zn _0.2 Fe ₂ O ₄ ferrite nanocomposites

The nanocomposite of hard (BaFe ₁₂ O ₁₉ )/soft ferrite (Ni _0.8 Zn _0.2 Fe ₂ O ₄ ) was prepared by the sol-gel process, and then the polyaniline(PANI)/polypyrrole(PPY)-BaFe ₁₂ O ₁₉ /Ni _0.8 Zn _0.2 Fe ₂ O ₄ was produced by in situ polymerization method. The structures, morphology and electromagnetic properties of the samples were characterized by various instruments. XRD, TEM, and FTIR analysis indicated that BaFe ₁₂ O ₁₉ /Ni _0.8 Zn _0.2 Fe ₂ O ₄ ferrite were homogenously enwrapped by PANI(PPY) coating. The VSM and SDY-4 measurement show that the magnetic properties of the composites decreased with the increase in PANI(PPY) amount, However, the electrical conductivity is on the contrary. The electromagnetic properties of the composites were much better than BaFe ₁₂ O ₁₉ /Ni _0.8 Zn _0.2 Fe ₂ O ₄ in the frequency range of 2-15 GHz, which mainly depends on the dielectric loss of PANI(PPY). A minimum reflection loss of the PANI(PPY)-BaFe ₁₂ O ₁₉ /Ni _0.8 Zn _0.2 Fe ₂ O ₄ ferrite nanocomposite is -19.7 dB(-21.5 dB) at the frequency of 7.3 GHz (10.7 GHz).