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      https://www.ias.ac.in/article/fulltext/boms/037/03/0497-0504

    • Keywords

       

      Nanocomposites; magneto-dielectric effect; two-phase inhomogeneous medium; Maxwell–Wagner effect.

    • Abstract

       

      Composites comprising of nanoparticles of Ni0.5Zn0.5Fe2O4 (NZF) and BaTiO3 (BT), respectively were synthesized by a chemical method. The particles had diameters in the range of 15–31 nm. NZF was prepared by a coprecipitation technique. This was soaked in a sol containing BT. Compositions synthesized were 𝑥NZF-(1 - 𝑥) BT, where 𝑥 = 0.7, 0.5 and 0.3, respectively. The composites showed ferromagnetic hysteresis loops due to NZF phase. The analysis of coercivity variation as a function of temperature gave blocking temperatures in the range of 306–384 K depending on the diameter of the ferrite nanoparticles. This implied that superparamagnetic interactions are above these temperatures. The nanocomposites also exhibited ferroelectric behaviour arising due to the presence of BT. The remanent polarization of the samples was small. This was adduced to the nanosize of BT. The specimens showed magneto-dielectric (MD) effect in the magnetic field range 0–0.7 Tesla. The MD parameter measured at the maximum magnetic field was around 2\%. This was one order of magnitude higher than that reported so far in similar composite systems. This was explained on the basis of a two-phase inhomogeneous medium model with an interface between them, the phases possessing drastically different electrical conductivities.

    • Author Affiliations

       

      Shilpi Banerjee1 2 Partha Hajra1 Anindya Datta3 Asim Bhaumik2 Mykanth Reddy Mada4 Sri Bandyopadhyay4 Dipankar Chakravorty1

      1. MLS Professor’s Unit, Indian Association for the Cultivation of Science, Kolkata 700032, India
      2. Department of Materials Science, Indian Association for the Cultivation of Science, Kolkata 700 032, India
      3. University School of Basic and Applied Science (USBAS), Guru Govind Singh Indraprastha University, New Delhi, India
      4. School of Materials Science and Engineering, University of New South Wales, Kensington, Sydney-2052, Australia
    • Dates

       
  • Bulletin of Materials Science | News

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