Influence of ultrasonic radiation on the structural, magnetic, electrical, and catalytic properties of NiFe2O4 nanoparticles

Adsorptive Remediation of Hazardous Crystal Violet Dye using Ni1‐xZnxFe2O4 Magnetic Nanocomposites

“…The density of pure nickel ferrite as measured by X-rays is found to be 5.28 g/cm 3 (as previously published [23] ), closely matching its previously reported value of 5.38 g/cm 3 . It is found that zinc substitution causes the X-ray density of NiÀ Zn ferrites to drop from 5.3 g/cm 3 to 5.1 g/cm 3 .…”

“…Examination of data in Table ( 1) demonstrated that, all the prepared adsorbents are in nanoscale, which later confirmed by HRTEM. In addition, the crystallite size of the pure nickel ferrite particles is measured to be 17.0 nm, [23] while on Zn 2 + substitution, it was seen to have increased to an average value of 23.7 nm. Furthermore, the value of d x linearly grew as crystallite size is increased, indicating minimal porosity, surface area.…”

“…The XRD diffractograms of the nano-crystalline Ni 1À x Zn x Fe 2 O 4 (x = 0.1, 0.5, and 0.9) calcined at 800 °C are demonstrated in Figure 1. XRD of the samples with x values of 0.1, 0.5, and 0.9 [23] 0.1, 0.5, and 0.9) nanocomposites calcined at 800 °C.…”

“…The de Boer and Verwey mechanism, which includes electron exchange between the same element ions in different valence states, can help to explain electric conduction in NiÀ Zn ferrites. [22,23] Zinc volatilization at high temperatures produces Fe 2 + ions in NiÀ Zn ferrite, and Ni 2 + can be oxidized to Ni 3 + throughout the sintering process [24,25] . Because Fe 2 + and Ni 3 + ions have a clear preference for inhabiting octahedral (B) sites, electron exchange between Fe 2 + and Fe 3 + ions, as well as hole transfer between Ni 3 + and Ni 2 + ions, is anticipated to be the conduction mechanism.…”

“…[48] The concentration of Zn ions on the A-site to the concentration of Ni ions on the B-sites determines hole x Activation energy (eV) 0 0.390 a 0.1 0.400 0.5 0.499 0.9 0.568 *a data previously published. [23] ChemistrySelect conduction in NiÀ Zn ferrite. As Zn 2 + content decreases, the Ni 2 + and Ni 3 + ions' number on the B-sites increases.…”