Structural, magnetic and electrical properties of nano NiCrxFe2-xO4 synthesized by flash auto combustion method

A M A Henaish, O M Hemeda, B I Salem, Fatma S El-Sbakhy, Talal Khalass
2019 Journal of Physics, Conference Series  
The spinel Nano-ferrite system NiCr x Fe 2-x O 4 (where x=0.0, 0.2, 0.4, 0.6, 0.8 and 1.0) have been prepared using flash auto combustion method. The XRD pattern confirms the formation of spinel Ni-Cr ferrite for the as-prepared samples. Electrical properties of as-prepared samples such dielectric constant and AC resistivity were studied in the temperature range (288-773 K). It was observed that the AC resistivity increases by increasing Cr content and decreases by increasing frequency. The DC
more » ... lectrical resistivity was found to increase by increasing Cr content from 25*10 6 to 136*10 6 Ω.cm, whereas it was found to decrease with increasing temperature. VSM was used to study the magnetic properties of Ni-Cr ferrite at room temperature. It was found that, with increasing Cr content the (Ms) saturation magnetization decreased from 28 to 3 emu/g whereas coercivity increased from 188 to 666 (G).The magnetic moment of the system and Curie temperature decreased by increasing Cr substitution. 2 Experimental producers. Nano-ferrite samples with the chemical formula NiCr x Fe 2-x O 4 (x=0.0, 0.2, 0.4, 0.6, 0.8 and1.0) were prepared by using the flash auto combustion method. The analytical grade of Fe(NO 3 ) 3 .9H 2 O, Cr(NO 3 ) 3 .9H 2 O, Ni(NO 3 ) 2 .6H 2 O and Urea [Co(NH 2 ) 2 ] as the fuel were used. The amount of urea was calculated using charge neutrality equations [37] . The chemicals were weighed in the required stoichiometric proportions, good mixed together for a few minutes and then heated on a hot plate magnetic stirrer at 80 o C for half hr. Thermal dehydration resulted in a highly viscous liquid. With more heating, the viscous liquid swelled and auto-ignited to harvest powder. The reaction was very fast and a fine powder was obtained [38] . The structural characterizations of all samples were carried out by X-ray diffractometer (Shimadzu XRD6000, Japan) (XRD) and confirms the formation of spinel structure. XRD data were taken at room temperature using Cu-Kα radiation source (λ = 1.5405 Å). The AC resistivity and dielectric constant were measured as a function of temperature using RLC Bridge type MC2811C RLC Bridge. The DC resistivity was measured using electrometer type 610C Kethely solid-state electrometer. The magnetic properties were measured at room temperature using vibrating sample magnometer (VSM) operating system v 1.6 control software Oxford OX8JTL England.
doi:10.1088/1742-6596/1253/1/012025 fatcat:4bs5k5hit5hmnoowibce7uddkq