Sol–gel auto-ignition fabrication of Gd3+ incorporated Ni0.5Co0.5Fe2O4 multifunctional spinel ferrite nanocrystals and its impact on structural, optical and magnetic properties

Abstract

Monophasic nanocrystals of rare earth gadolinium (Gd 3+) ion doped nickel-cobalt ferrite, Ni 0.5 Co 0.5 Gd y Fe 2−y O 4 (y = 0.00, 0.025, 0.050, 0.075, 0.100 and 0.125) have been synthesized by l-ascorbic acid assisted sol-gel auto-ignition process. Thermogravimetric and differential scanning calorimetry, X-ray diffraction, Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM) with selected area electron diffraction (SAED) patterns, ultraviolet-visible spectrophotometry and vibrating sample magnetometer were employed to characterize the microstructure, optical and magnetic properties. Structural investigations verified the presence of cubic spinel phase short of any contamination peak. The average crystallite size was seen in nano-regime dimensions and well confirmed by TEM results. SAED patterns showed bright and intense ring of (311) plane revealed the establishment of spinel ferrite nanocrystals. Lattice constant (a) increases steadily with the rise in Gd 3+ content following the Vegard's law. FTIR spectra confirmed the creation of spinel ferrite structural geometry. Saturation magnetization (M s) and a remanence magnetization (M r) decreased from 29.77 to 20.78 emu/g and 21.62 to 15.79 emu/g, respectively, with increasing the Gd 3+ content. However, coercivity (H c) is significantly increased. The highest value of H c = 1132 Oe was found for y = 0.075 sample. The reduction in M s values can be justified owing to the replacement of Fe 3+ existing at the octahedral [B]-sites by the Gd 3+ ions which is paramagnetic at room temperature. The elucidation of magnetic parameters with Gd 3+ doping was attributed to the discrepancy of anisotropy constant, the paramagnetic nature of Gd 3+ and crystallite size effect.

Catalytic degradation of toxic organic dye using an aluminum‐doped Cu0.4Zn0.6‐xAlxFe2O4 (x = 0.0, 0.2, 0.4, 0.6) spinel ferrite in a photo‐Fenton system

“…The phase purity of spinel Cu 0.4 Zn 0.6‐x Al x Fe 2 O 4 (x = 0.0, 0.2, 0.4, 0.6) was confirmed by using XRD data. Exhibit 3 shows eight sharp peaks attributed to (220), (311), (400), (422), (511), (440), (533), and (444) planes, Fd‐3 m space group (JCPDS 10‐0325) confirming the spinel ferrite configuration (Debnath et al., 2019; Hegazy et al., 2019; Pawar et al., 2020) where, primarily the high‐intensity sharp peak of (311) plane indicates the face‐centered cubic spinel phase (Chahar et al., 2021). Moreover, the presence of additional peaks at 2θ = 24.1, 49.2, and 64.1° for α‐Fe 2 O 3 secondary phase (JCPDS file no.…”

“…(444) planes, Fd-3 m space group (JCPDS 10-0325) confirming the spinel ferrite configuration (Debnath et al, 2019;Hegazy et al, 2019;Pawar et al, 2020) where, primarily the high-intensity sharp peak of (311) plane indicates the face-centered cubic spinel phase (Chahar et al, 2021). Moreover, the presence of additional peaks at 2θ = 24.1, 49.2, and 64.1 • for α-Fe 2 O 3 secondary phase (JCPDS file no.…”

Lanthanum substituted Ni-Zn ferrite (Ni0.75Zn0.25Fe2O4) nanomaterial and its composite with rGO for degradation of binary dyes under visible light irradiation

“…The mineralization of binary synthetic coloring agents (MB and MO) under visible light irradiation was used to test the photocatalytic efficiency of the synthesized materials. [32]. Citric acid was used as an organic fuel and it provides a platform for the redox reaction which occurs between the reactants during the course of the combustion process.…”

Studies on Structural Properties of Ytterbium (Yb3+) Substituted Mg–Cu–Zn Nano‐ferrites

“…In recent years, a considerable amount of research has been carried out on ferrites because of their applications in non‐resonant devices, radio frequency circuits, high‐quality filters, rod antennas, transformer cores, and read/write heads for high‐speed digital tapes. [ 1–5 ] The rapid development of ferrites for the new fields of computer circuits and microwave components promises a greater effect on the daily lives of engineers and the public in the near future. The number of parameters plays an important role in deciding the suitability of a ferrite for a particular application.…”