Impact of lanthanum ions on magnetic and dielectric properties of cobalt nanoferrites

• Published in: Journal of materials science. Materials in electronics Vol. 31; no. 12; pp. 9783 - 9795
• Main Authors: Kartharinal Punithavathy, I., Rajeshwari, A., Johnson Jeyakumar, S., Lenin, N., Vigneshwaran, B., Jothibas, M., Arunkumar, B.
• Format: Journal Article
• Language: English
• Published: New York Springer US 01.06.2020; Springer Nature B.V
• Subjects: Characterization and Evaluation of Materials; Chemistry and Materials Science; Cobalt; Crystals; Dielectric loss; Dielectric properties; Diffraction patterns; Ferromagnetism; Fourier transforms; Grain boundaries; Hysteresis loops; Infrared radiation; Lanthanum; Magnetic properties; Magnetometers; Materials Science; Metal oxides; Optical and Electronic Materials; Photoelectrons; Sol-gel processes; Spectrum analysis; Spinel; Ultraviolet reflection
• ISSN: 0957-4522; 1573-482X
• DOI: 10.1007/s10854-020-03523-3

Lanthanum-doped cobalt nanoferrites CoLa X Fe 2− X O 4 ( X  = 0.00 to 0.08) were synthesized by using sol–gel method. A cubic spinel structure was confirmed by using X-ray diffraction pattern. A band obtained at 583 cm −1 recorded by Fourier transform infrared spectrum confirmed the presence of metal oxide spinel nanoferrites. The bandgap energy has increased with addition of La 3+ ions by using ultraviolet diffuse reflectance spectrum. The grain boundary contribution is greater than that of grain contribution due to small crystal size, which was confirmed by an impedance analysis. The dielectric constant and dielectric losses decreased with increasing frequencies. The binding energy of La, Co, Fe and O were determined by X-ray photoelectron spectroscopy. The magnetic studies were analyzed through vibrating sample magnetometer. The hysteresis loop revealed the soft ferromagnetic nature.