Synthesis, characterization, and dielectric studies of magnetic iron oxide nanoparticles.

There are many nanoparticle preparation techniques such as the biological approach sol-gel method and physical methods, etc. However, the co-precipitation approach requires few chemical reagents and reaction time as well as produces highly pure products with comparatively lower costs among the available techniques. In present work co-precipitation method is use to synthesize magnetic iron oxide (Fe₃O₄) nanoparticles, followed by characterization to check its applicability and the presence of undesired substrate. UV–visible spectroscopy, scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), X-ray diffraction (XRD), and Fourier-Transform Infrared Spectroscopy (FTIR) were examined to determine the synthesized Fe₃O₄ nanoparticles. The nanoparticles' sizes lies between 1 nm to 100 nm, according to the SEM and HR-TEM analyses. XRD measurements verified the crystalline characteristics of the Fe₃O₄ nanoparticles. Dielectric spectroscopy of synthesized Fe₃O₄ nanoparticle pellets has been investigated at a wide frequency range 0.1 to 10⁵ Hz. Capacitance and dielectric permittivity of Fe₃O₄ nanoparticles decrease continuously with frequency as dipole gets less time to orient in the field. The dielectric permittivity of Fe₃O₄ pellets increases up to 3 mm thickness and subsequently drops, perhaps because a rise in resistance. The electrical conductivity of Fe₃O₄ rises exponentially with frequency. According to the dielectric studies, the dielectric permittivity and electrical conductivity of Fe₃O₄ are greatly dependent on the thickness and extent of frequency. Additionally, the dielectric impedance of Fe₃O₄ pellets has also been investigated as a function of frequency. [ABSTRACT FROM AUTHOR]