| publication name | Cr-substituted Ni–Zn ferrites via oxalate decomposition.Structural, electrical and magnetic properties |
|---|---|
| Authors | M.A.Gabal , Y.M.AlAngari , F.A.Al-Agel |
| year | 2015 |
| keywords | Cr-substitution NiZn ferrite Susceptibility Hysteresis Conductivity |
| journal | Journal of Magnetism and Magnetic Materials |
| volume | 391 |
| issue | Not Available |
| pages | 108-115 |
| publisher | Not Available |
| Local/International | International |
| Paper Link | Not Available |
| Full paper | download |
| Supplementary materials | Not Available |
Abstract
A seriesofCr-substitutedNi–Zn ferrites;Ni0.8Zn0.2CrxFe2xO4 (x¼0.0–1.0)werepreparedviaoxalate decomposition routetocharacterizetheeffectofCr-substitutiononstructural,magneticandelectrical properties. ThepreparedpowderswerecharacterizedusingX-raydiffraction(XRD),Fouriertransform infrared(FT-IR)andtransmissionelectronmicroscopy(TEM).XRDindicatedsingle-phasecubicferrites. The latticeparameters(aExp) exhibitedagradualdecreasewithincreasingchromium,attributedtothe smaller ionicradiiofCr3þ substituent. Accordingtotheobtainedstructuraldata,anappropriatecation distribution wassuggestedandfortified throughFT-IRspectroscopybesidesmagneticandelectrical measurements. TEMimageshowedagglomeratedcubiccrystalswithanaveragesizeofabout20nm. Vibrating samplemagnetometer(VSM)measurementsindicatedminimalhysteresischaracteristicfor soft magneticmaterial.Thedecreaseinsaturationmagnetization(Ms) withCr-substitutionwasdiscussed in viewofNeel’s twosub-latticemodel.ThechangeinthecoercivitywithCr-contentwasdiscussedin view ofestimatedcationdistributionandmagnetizationvalues.TheobviousfallintheCurietempera- ture, estimatedfrommolarsusceptibilitymeasurements,withincreasingCr-concentrationswasassigned to thegradualreplacementofFe3þ ions ontheoctahedralsitesbyparamagneticCr3þ ions. ac-con- ductivity asafunctionofbothfrequencyandabsolutetemperatureexhibitedasemi-conductingbeha- vior.ThedecreaseinconductivitywithincreasingCr-contentwasattributedtothepreferentialoccu- pation ofCr3þ ions byoctahedralsiteswhichreplacingFe3þ ions andlimitingFe2þ –Fe3þ conduction.