محمد عبد الفتاح محمد جبل
أستاذ
Cr-substituted Ni–Zn ferrites via oxalate decomposition.Structural, electrical and magnetic properties
Journal of Magnetism and Magnetic Materials • 2015
معلومات البحث
المؤلفون
M.A.Gabal , Y.M.AlAngari , F.A.Al-Agel
الكلمات المفتاحية
Cr-substitution
NiZn ferrite
Susceptibility
Hysteresis
Conductivity
المجلة العلمية
Journal of Magnetism and Magnetic Materials
الناشر
Not Available
المجلد
391
العدد
Not Available
الصفحات
108-115
publication.type
International
رابط البحث
Not Available
المواد المرفقة
Not Available
الملخص
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.
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.