Effect of microwave heat treatment on pure phase formation of hydrothermal synthesized nano NiMg ferrites

ABSTRACT

The present work mainly focuses on the preparation of magnesium-doped nickel ferrite nanoparticles via hydrothermal technique. Diffraction pattern attributes the formation of pure cubic spinel phases after microwave heating the samples at 500 °C for 10 min. In addition to the diffraction study, the removal of lepidocrocite (γ-FeO (OH)) signal in an infrared spectrum also confirms the phase purity due to microwave heating. Larger optical band gap (E_g) values are acquired for nanostructures varying between 1.73 and 1.86 eV. The surface morphology is analyzed using transmission electron microscope. The obtained particle sizes are in the range of ∼50–85 nm. The M-H loop analysis shows that 50% of Mg-dopant in Ni-ferrite system exhibits the highest saturation magnetization ∼191 emu/g. The behavior of complex dielectric modulus is illustrated in the specific frequency range of 100 Hz to 5 MHz for investigating the space charge polarization mechanism.

KEYWORDS:

• Ferrites
• microwave synthesis
• optical properties
• impedance analysis

Acknowledgments

This work is financially supported by DRDO Project, No. ERIP/EP/1103015/M/01/1484/ dtd.20.06.13, New Delhi and thankful to Prof. S. Kalainathan for providing LCR bridge facility. Also acknowledge to SIF at SAS, VIT University, Vellore for providing XRD and FTIR facilities. I am specially thankful to Dr. S. Majunatha Rao, HCU, Hyderabad for providing VSM facility.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

The present work was supported by a funding agency of DRDO [project number ERIP/EP/1103015/M/01/1484/ dtd.20.06.13].