Enhanced Magnetic Behavior of Chemically Prepared Multiferroic Nanoparticles of GaFeO3 in (GaFeO3)_(0.50) (Ni_(0.4)Zn_(0.4)Cu_(0.2)Fe2O4)_(0.5) Nanocomposite

摘要

Nanoparticles of GaFeO3 (GFO) and Ni_(0.4)Zn_(0.4)Cu_(0.2) Fe2O4 (NZCF) and their nanocomposite [(GaFeO3)_(0.50) (Ni_(0.4)Zn_(0.4)Cu_(0.2)Fe2O4)_(0.50), GFONZCF] were prepared by chemical route. Nanoparticles of GFO were synthesized by sol-gel route, and those of NZCF were prepared by chemical coprecipitation method. The nanoparticles of GFO were incorporated in the matrix of NZCF by coprecipitating the salts required for NZCF in the presence of GFO particles, followed by subsequent washing and heat treatment at 500 °C. X-ray diflractograms (XRDs) were recorded to confirm the formation of the desired crystallographic phases of the samples. The sizes of the nanoparticles were estimated from the broadening of the well-defined peaks using the Debye—Scherrer equation. The nanoparticle size and its distribution, crystallographic phase, nanocrystallinity, and so on were studied by a high-resolution transmission electron microscope (HRTEM), and the extracted results were in good agreement with those obtained from the XRD patterns. The static and dynamic magnetic measurements were carried out. The observations of field-cooled (FC), zero-field-cooled (ZFC) magnetizations, and hysteresis loops (M-H loop) in the temperature range of 300 to 2 K were carried out in the static measurements. The static magnetic data were analyzed to evaluate the particle size, nanocrystalline anisotropy, and so on, and the agreement of these evaluated data are quite satisfactory, so far as the extracted results obtained from XRD and HRTEM are concerned. The maximum magnetization of the GFO sample has been drastically enhanced by incorporating them in the matrix of NZCF. Also, the nature of variation of the magnetization in all cases of FC, ZFC, and M-H curves of the nanoparticles of GFO has been drastically modulated by the NZCF. The dynamic magnetic measurements include the measurements of ac magnetization versus excitation curves, hysteresis loops at different frequencies at room temperatures, and so on. The remarkable enhancement of magnetization of the multiferroic system of GFO by the encapsulation of NZCF would be quite interesting for various applications.