Enhanced coercivity of NiFe_1–xDy_xCrO₄ ferrites synthesised by glycine-nitrate combustion method

ABSTRACT

The present work was focused on the effect of small amounts of Dy doping on the structural and magnetic properties of Ni-Cr ferrite materials. All the ferrites possess cubic symmetry corresponding to the space group $Fd\overline{3}m$ with small amounts of secondary phase DyFeO₃. No regular trend in the lattice parameter a with Dy doping has been observed. Room temperature magnetisation results, obtained from Vibrating Sample Magnetometer measurements, showed a decrease in saturation magnetisation with Dy doping. Enhanced coercivity in undoped Ni-Cr ferrite is observed which was several orders of magnitude higher than that of the reported bulk material. Substitution of Dy in Ni-Cr ferrite further enhances coercivity thereby making the materials magnetically more hard.

KEYWORDS:

• Combustion method
• Rietveld refinements
• SEM
• magnetic properties

Acknowledgements

Authors are thankful to University Grants Commission, New Delhi for financial support vide Ref. No. 20/12/2015 (11) EU-V (Sr. No. 21215101B1). Authors are also thankful to Director, Advanced Materials Research Centre, IIT Mandi, for recording XRD. Thanks are also due to Prof. Ramesh Chandra, Institute Instrumentation Centre, Indian Institute of Technology, Roorkee, for recording EDX and SEM. Thanks are also due to Director, Central Instruments Facility, Indian Institute of Technology, Guwahati, for carrying out M-H magnetic measurements.

Disclosure statement

No potential conflict of interest was reported by the authors.