DC electrical resistivity and dielectric properties of Ni–Zn nanoferrite synthesized via autocombustion route
- Resource Type
- Authors
- K. Trinath; M. Siva Ram Prasad; B. Rajesh Babu; K. V. Ramesh
- Source
- Indian Journal of Physics. 90:417-428
- Subject
- 010302 applied physics
Materials science
Scanning electron microscope
Spinel
General Physics and Astronomy
Sintering
02 engineering and technology
Dielectric
engineering.material
Atmospheric temperature range
equipment and supplies
021001 nanoscience & nanotechnology
01 natural sciences
Electrical resistivity and conductivity
visual_art
0103 physical sciences
visual_art.visual_art_medium
engineering
Ferrite (magnet)
Ceramic
Composite material
0210 nano-technology
- Language
- ISSN
- 0974-9845
0973-1458
Polycrystalline nickel–zinc nanoferrite with composition Ni0.5Zn0.5Fe2O4 has been prepared through the nitrate–citrate gel autocombustion method. The as-prepared powders have been annealed at temperatures of 800, 900 and 1000 °C for 4 h and characterized for spinel phase using X-ray diffraction. Pelleted and toroidal samples of Ni0.5Zn0.5Fe2O4 have been sintered at the above temperatures for 4 h in air atmosphere followed by natural cooling to room temperature. Surface morphology of the annealed powders has been recorded using scanning electron microscope. Scanning electron micrographs of the annealed powders display the presence of nearly agglomerated spherical nanoparticles. Temperature variation of the DC electrical resistivity of sintered pellets has been studied in the temperature range of room temperature to 150 °C. The electrical resistivity of the samples in the present study is observed to be larger than those for the nickel–zinc ferrites prepared through conventional ceramic process, for all temperatures of sintering. Such ferrite materials with high resistivity can be used as magnetic cores, which are operable over wide frequency range. The initial magnetic permeability of Ni0.5Zn0.5Fe2O4 increases with the increase in sintering temperature. Initial magnetic permeability and dielectric measurements for all samples have been carried out in the frequency range of 1 kHz to 13 MHz.