Study of Magnetoelectric Properties of Composites Based on Magnetic Particles of Fe₂O₃ and Bentonite Using Percolation Theory

The paper presents the results from studies of the electrical and magnetic properties of an inhomogeneous percolated medium based on the theory of percolation. The application of this theory has a wide and varied range. Examples include hopping conductivity in semiconductors, properties of porous materials, etc. It was found that, with approaching the percolation threshold p_c = 0.35, the resistivity decreases, and the electrical conductivity increases accordingly. An increasing number of individual ferromagnetic nanogranules in (p)–Fe₂O₃–(1–p) (MBT) composites merge with the formation of individual Fe₂O₃ clusters in the bentonite matrix, which combine to form a continuous network of clusters. This is due to the fact that the resistivity ρ of the composite is mainly determined by the magnetic component of the latter.