Electrical and Magnetic Properties of Mg-Cr and Co-Cr Nano- Ferrites Synthesized by Citrate-gel Method

Raghasudha, M.; Ravinder, D.; Veerasomaiah, P.
April 2016
Solid State Phenomena;2016, Vol. 241, p69
Academic Journal
The work deals with the study of electrical and magnetic properties of Magnesium- Chromium and Cobalt-Chromium Nano Ferrites for their potential applications synthesized by Citrate-Gel auto-combustion method. Structural Characterization of prepared Nano ferrites was performed using XRD, SEM, EDS and TEM. XRD patterns confirmed the formation of homogeneous single phased cubic spinel belonging to the space group Fd3m (in agreement with ICSD Ref. data). It is found that crystallite size of Mg-Cr ferrites was in the range of 7-23nm and that of Co-Cr nano ferrites in the range of 6-12 nm. Structural morphology of both the ferrites was studied by SEM (Scanning Electron Microscopy) and TEM (Transmission Electron Microscopy). Elemental compositional analysis was carried out by EDS. Electrical properties such as D.C. resistivity of prepared Mg-Cr and Co-Cr nano ferrites were studied by two probe method. The dielectric measurements as a function of frequency at room temperature were performed in the frequency range of 20Hz to 2MHz using LCR meter. Various dielectric parameters like dielectric constant (ε'), dielectric loss (ε") and dielectric loss tangent (tan d) were measured as a function of frequency. The magnetization measurements of the prepared nano ferrite samples were carried out at room temperature in the applied field of ±15KOe using Vibrating Sample Magnetometer (VSM). From the obtained M-H loops, various magnetic parameters such as Saturation Magnetization (Ms), Coercivity (Hc) and Remanence Magnetization (Mr) were measured. Magnetization as a function of field (±10T) at 5K, 25K, 300K temperatures was measured using VSM. Super-paramagnetic nature of some specified samples in Mg-Cr nano ferrites system was investigated from the temperature dependence of both the field cooled (FC) and the zero-field cooled (ZFC) magnetization measurements under a field of 100 Oe in the temperature range 5K to 350K. From the results of D.C. resistivity measurements it is observed that the resistivity decreases with increase in temperature for both Mg-Cr and Co-Cr nano-ferrites suggesting the semiconducting behavior of the samples. Dielectric measurements suggest that the conduction in the ferrite systems may be due to the polaron hopping mechanism. The low loss tangent values at high frequency show the potential applications of these materials in high frequency microwave devices. Mg-Cr Nano ferrites were synthesized yielding narrow hysteresis loops which are the characteristic of very soft magnetic materials that are desirable for their utility in Transformers, Inductor cores, Microwave devices and Magnetic shielding. Hysteresis loops of Co-Cr nano ferrites show the medium hard magnetic behavior of the materials. MgFe2O4 shows superparamagnetic behavior above room temperature and MgCr0.9Fe1.1O4 shows superparamagnetic behavior with the blocking temperature 94.5K. Hence these nano ferrites find applications in targeted drug delivery and in Magnetic Resonance Imaging (MRI) in biomedical field. The observed results can be explained in detail on the basis of composition and crystallite size.


Related Articles

  • Modification of the Magnetic Properties of Co2Y Hexaferrites by Divalent and Trivalent Metal Substitutions. Mahmood, Sami H.; Zaqsaw, Muna D.; Mohsen, Osama E.; Awadallah, Ahmad; Bsoul, Ibrahim; Awawdeh, Mufeed; Mohaidat, Qassem I. // Solid State Phenomena;2016, Vol. 241, p93 

    The present study is concerned with the fabrication and characterization of Me2Y substituted hexaferrites, Ba2Me2Fe12-xTxO22 (Me = Co2+, Mg2+, and Cr2+, and T = Fe3+, and Ga3+). The samples were prepared by the conventional ball milling technique and sintering at 1200° C. The effect of the...

  • Nanoferrites of Transition Metals and Their Catalytic Activity. Sharma, J. K.; Srivastava, Pratibha; Singh, Gurdip; Virk, H. S. // Solid State Phenomena;2016, Vol. 241, p126 

    Recent applications of transition metal nanoferrites as catalyst in thermal decomposition of ammonium perchlorate (AP) and combustion of composite solid propellant (CSP), have been reviewed. Catalytic applications include the use of mainly cobalt, nickel, copper, zinc, manganese, cadmium...

  • Super-paramagnetic Nanoparticles with Spinel Structure: A Review of Synthesis and Biomedical Applications. Galvãoa, Wesley S.; Neto, Davino M. A.; Freire, Rafael M.; Fechine, Pierre B. A. // Solid State Phenomena;2016, Vol. 241, p139 

    The study of ceramic materials has attracted the attention of many researchers due to the possibility of their use in nanotechnology. The spinel ferrites form a large group of materials with a broad range of applications. Some examples include electronic devices such as high-frequency...

  • Editors' Note. Virk, H. S.; Jotania, R. B. // Solid State Phenomena;2016, Vol. 241, preceding p2 

    No abstract available.

  • Magnetic Nanoparticles: Synthesis and Properties. Rewatkar, Kishor G. // Solid State Phenomena;2016, Vol. 241, p177 

    The discovery of novel materials, processes, and phenomena at the nanoscale and the development of new experimental and theoretical techniques for research provide fresh opportunities for the development of innovative nano-systems and nanostructured materials. Nanomaterials with tailored unique...

  • Hexagonal Ferrite Fibres and Nanofibres. Pullar, Robert C. // Solid State Phenomena;2016, Vol. 241, p1 

    Hexagonal ferrites, or hexaferrites, are hugely important materials commercially and technologically, with common applications as permanent magnets, magnetic recording and data storage media, components in electrical devices operating at wireless frequencies, and as GHz electromagnetic wave...

  • Studies on Internal Friction and Curie Temperature of NiMgCuZn Spinel Ferrites for Micro-Inductor Applications. Varalaxmi, N.; Sivakumar, K. V.; Virk, H. S. // Solid State Phenomena;2016, Vol. 241, p202 

    Three series of NiMgCuZn ferrites were prepared by conventional double sintering ceramic process. The formation of single phase in these ferrites was confirmed by X-ray diffraction. A brief review of the important investigations carried out on the internal friction behaviour of NiMgCuZnFe2O4, in...

  • Influence of Ca-doping on Structural, Magnetic and Dielectric Properties of Ba3Co2-xCaxFe24O41 Hexaferrite Powders. Solanki, N.; Jotania, R. B. // Solid State Phenomena;2016, Vol. 241, p226 

    Influence of Ca substitution on structural, magnetic and dielectric properties of Ba3Co2-xCaxFe24O41 (where x = 0.0, 0.2, 0.4, 0.6, 0.8 and 1.0), prepared by Sol-Gel auto-combustion method, has been investigated in present studies. The obtained powder was sintered at 950 ºC for 4 hrs. in the...

  • Mössbauer evaluation of cobalt ferrite nanoparticles synthesized by forced hydrolysis. Hamdeh, H. H.; Hikal, W. M.; Taher, S. M.; Ho, J. C.; Thuy, N. P.; Quy, O. K.; Hanh, N. // Journal of Applied Physics;3/15/2005, Vol. 97 Issue 6, p064310 

    Spinel cobalt ferrite in the form of nearly spherical particles, having a narrow range of particle size around 7.6 nm, was produced by forced hydrolysis. Between the magnetization blocking temperature of 180 K and the Mössbauer blocking temperature of 270 K, the magnetic anisotropy energy...


Read the Article


Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics