Structural and Magnetic Studies of Cr3+ Substituted Nickel Ferrite Nanomaterials Prepared by Sol-Gel Auto-Combustion

Abstract

The present study envisages the preparation of chromium substituted Nickel ferrite NiCrxFe2−xO4 (x = 0~1.0) powders by a sol-gel auto-combustion method. X-ray diffraction analysis (XRD) showed that the specimens with x > 0.2 exhibited a single-phase spinel structure, and that more content of Cr within a specimen is favorable for the synthesis of pure Ni-Cr ferrites. The lattice parameter decreased with an increase in the Cr concentration. The sample without calcining exhibited a good crystallinity. Scanning Electron Microscopy (SEM) showed the formation of ferrite powders nano-particles, and that the substitution of Cr weakened the agglomeration between the particles. Mössbauer spectra of NiCrxFe2−xO4 showed two normal Zeeman-split sextets that displayed a ferrimagnetic behavior. Furthermore, the spectra indicated that iron was in the Fe3+ state, and the magnetic hyperfine field at the tetrahedral tended to decrease with an increase in the Cr substitution. The saturation magnetization decreased by the Cr3+ ions, and reached a minimum value (Ms = 4.46 emu/g). With an increase in the annealing temperature, the coercivity increased initially, which later decreased.

Effect of Cr3+ substitution on magnetic and electrical properties of (Ni0.3Cu0.7) Fe2O4 spinel ferrites

“…It was observed that magnetization shows a non-collinear ferrimagnetic structure for x = 0.5 − 0.9 indicated a magnetic phase change. Ni 1−x Cr x Fe 2 O 4 (x = 0.0 − 1.0) prepared by sol-gel auto combustion technique in single phase form for x > 0.2 are reported [11]. Scanning electron microscopy (SEM), results of the samples revealed the formation of nano-particles.…”

Applications of nano-materials in diverse dentistry regimes

“…Metal oxide and chloride are two precursors that are usually deployed in the sol-gel procedure. [66][67][68][69] Aerwards, the precursors are scattered in a host liquid by stirring, shaking, or sonicating. The nal system comprises a solid and a liquid phase.…”

Combustion Synthesis of NbB2–Spinel MgAl2O4 Composites from MgO-Added Thermite-Based Reactants with Excess Boron

“…There are four layers of AlO 6 octahedral chains along the c axis in one unit cell [12]. Fabrication of MgAl 2 O 4 and other spinel compounds like NiFe 2 O 4 and CoFe 2 O 4 by either solid-state or wet-chemistry reaction methods usually requires long processing time and complicated steps [14][15][16][17][18].With the merits of energy and time savings, simple operation, and high-purity products, combustion synthesis in the mode of self-propagating high-temperature synthesis (SHS) has been recognized as an alternative route to material synthesis and processing [19,20]. When the SHS process is combined with the aluminothermic or magnesiothermic reduction of metal oxides to generate Al 2 O 3 or MgO, the multistage combustion reaction represents an in situ approach to producing MgAl 2 O 4 -containing composites [21][22][23][24][25].…”

“…There are four layers of AlO 6 octahedral chains along the c axis in one unit cell [12]. Fabrication of MgAl 2 O 4 and other spinel compounds like NiFe 2 O 4 and CoFe 2 O 4 by either solid-state or wet-chemistry reaction methods usually requires long processing time and complicated steps [14][15][16][17][18].…”