Structural electrical and magnetic properties of mg zr co substituted ni0 5zn0 5fe2o4

Journal of Science: Advanced Materials and Devices (2019) 310e318 Contents lists available at ScienceDirect Journal of Science: Advanced Materials and Devices journal homepage: www.elsevier.com/locate/jsamd Original Article Structural, electrical and magnetic properties of Mg-Zr co-substituted Ni0.5Zn0.5Fe2O4 K Jalaiah a, b, *, K Chandra Mouli c, K Vijaya Babu d, R.V Krishnaiah e a Chebrolu Engineering College, Chebrolu, Guntur, 522212, India Department of Physics, Andhra University, Visakhapatnam 530003, India c Department of Engineering, Physics, Andhra University, Visakhapatnam 530003, India d Advanced Analytical Laboratory, Andhra University, 530003, India e Institute of Aeronautical Engineering and Technology, Hyderabad, 500043, India b a r t i c l e i n f o a b s t r a c t Article history: Received October 2018 Received in revised form 15 December 2018 Accepted 16 December 2018 Available online 23 December 2018 Zr and Mg co-substituted Ni0.5Zn0.5Fe2O4 ferrites have been synthesized by the sol-gel auto-combustion method The X-ray diffraction patterns evidenced the single phase cubic spinel structure The lattice parameter and cell volume are in resemblance trend with the variation of the dopant concentration The similar trend is observed for the crystallite and particle size The porosity and sintered density, however, vary in an opposite way with a variation of the dopant concentration The same variation is found for the drift mobility and DC resistivity The Arrhenius graphs of DC resistivity exhibit the semiconductor nature, for which the activation energy decreased with increasing the dopant concentration Moreover, as the dopant contents increased, the saturation magnetization, net magnetic moment and permeability are reduced, while the coercivity is reinforced These findings can be correlated with the variation of the porosity and grain size © 2018 The Authors Publishing services by Elsevier B.V on behalf of Vietnam National University, Hanoi This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/) Keywords: Ferrites XRD TEM SEM Permeability Saturation magnetization Anisotropy constant Introduction In early days iron based magnetic alloys are used in various applications However, their low resistivity made these materials inefficient at high frequencies, which encouraged the eddy current through them This wasted energy is created a serious problem that generated the heat in the circuit Hence, iron based magnetic materials are not favorable in high frequency applications Ferrite materials, in opposite, possess high resistivity and dielectric performances and not conduct the electric current readily The advantage of ferrites over magnetic alloys is that they formed a different combination of ferrites with transition metals because the transition metals exhibit magnetic as well as semiconductor properties The porosity is an insignificant factor for ferrites so that the ferrites have been investigated for several years based on this issue In order to get the high resistivity of ferrites researchers * Corresponding author Chebrolu Engineering College, Chebrolu, Guntur, 522212, India E-mail address: kjalu4u@gmail.com (K Jalaiah) Peer review under responsibility of Vietnam National University, Hanoi choose different combination here we also choose a new combination with transition metals to get the high resistivity of ferrite material [1,2] Spinal ferrites are a class of magnetic oxides with the general formula of AB2O4 They are categorized as soft and hard ferrites according to their magnetic performance Soft ferrites are easily demagnetized without significant energy need, i.e only a small energy amount is wasted in the form of eddy currents to demagnetize the soft magnetic materials In case of hard ferrites, a significantly higher energy is needed to demagnetize This means that soft magnetic materials possess higher electrical resistivity, thus, they are used in inductors and transformers The magnetic oxides are made from the blend of iron, nickel, zinc, manganese oxides By using these oxides, different combinations of soft ferrites like Manganese-Zinc and Nickel-Zinc have been prepared For inductor cores, the magnetic permeability is the chief parameter [3,4] In order to improve the core performance at high frequency the grain size, which can be controled by the ferrite preparation technique, plays an important role The solid state ceramic technique is a general ferrite fabricated technique, in which the constituent oxides react at higher temperatures In this case, an unusual grain growth usually occurs due to the non stoichiometry https://doi.org/10.1016/j.jsamd.2018.12.004 2468-2179/© 2018 The Authors Publishing services by Elsevier B.V on behalf of Vietnam National University, Hanoi This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/)