27 مهر 1398
محمود ناصري

محمود ناصری

مرتبه علمی: دانشیار
نشانی:
تحصیلات: دکترای تخصصی / فیزیک-نانو
تلفن: 08132355404
دانشکده: علوم پایه

مشخصات پژوهش

عنوان
Structure and physical properties of Fe6 O8/ba Fe6 O11 nanostructure
نوع پژوهش مقاله چاپ شده
کلیدواژه‌ها
Nanostructure UV–vis absorption Magnetic properties EPR spectroscopy
سال
2016
مجله JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS
پژوهشگران محمود ناصری

چکیده

The thermaltreatmentmethodwasemployedtopreparebariumhexaferrite(Fe6 O8/Ba Fe6 O11) na- nostructure. Thismethodwasattemptedtoachievehigherhomogeneityofthe final product.Specimens of bariumhexaferritenanostructurewerecharacterizedbyvariousexperimentaltechniquesincluding X-raydiffraction(XRD),highresolutionFieldemissionscanningelectronmicroscope(FESEM)and Fourier transforminfraredspectroscopy(FT-IR). X-raydiffractionresultsshowedthattherewasnocrystallinityinthepredecessorandithadstill amorphous phase.Theformationsofcrystallinephasesofbariumhexaferritenanostructuresstarted from 673to973Kandthe final productshaddifferentcrystallitesizesrangingfrom29to48nm.The chemical analysisofthebariumhexaferritenanostructureswasperformedbyenergydispersionX-ray analysis(EDXA),demonstratedthatthebariumhexaferritenanostructurescontainedtheelementsofBa, Fe, andO.TheeffectofcalcinationtemperatureonbandgapenergywasstudiedbyUV–vis absorption spectra disclosedwhencalcinationtemperatureincreased,theappraisedbandgapenergyvaluesofthe BaFe12O19 nanostructures decreased.Theformednanostructuresexhibitedferromagneticbehaviors which wereconfirmed byusingavibratingsamplemagnetometer(VSM).ThetechniqueoftheElectron paramagnetic resonance(EPR)spectroscopywascarriedoutat300Konthecalcinedspecimensthat exhibitedthevariationoftheline-shapesofthespectraofwithcalcinationtemperature.