Spinel Nanoferrites Research Articles

A structural, morphological, optical and magnetic study of nickel-substituted zinc (Ni–Zn) ferrite nanoparticles synthesized via glycine assisted gel autocombustion synthesis route

The spinel NixZn(1-x)Fe2O4(x = 0.00, 0.25, 0.50)) ferrite nanoparticles were successfully synthesized by an innovative glycine assisted gel autocombustion synthesis route. The impact of substitution Ni2+cations on the structural, morphological, optical, and magnetic study of NixZn(1-x)Fe2O4nanostructures was studied. A single-phased cubic spinel type structure was confirmed by XRD with crystallite size ranging from 28 nm to 46 nm. The two absorption bands, ν1 and ν2 below 1000 frequency in FTIR spectra corresponding to the tetrahedral and octahedral sites respectively, demonstrated the signature of the spinel lattice of the prepared nanosamples. SEM micrographs revealed agglomerated hexagonal and nearly spherical nanoparticles of size less than 60 nm. TEM micrographs showed a cluster of single crystalline agglomerated nanoparticles and the average particle size estimated from TEM is in accordance with SEM results. SAED patterns confirmed the construct of spinel nanoferrite which proportionate with the XRD pattern. Furthermore, UV-DRS absorption spectroscopy was employed to investigate the optical characteristics of NixZn(1-x)Fe2O4 ferrite nanoparticles at room temperature. UV-DRS absorption spectra of all the samples displayed an exceptional visible light absorption band in the wavelength less than 600 nm. At room temperature M − H plots indicated that NixZn(1-x)Fe2O4 spinel ferrite exhibits paramagnetic (for x = 0%) and soft ferrimagnetic (for x = 25%, 50%) behaviour depending on the Ni2+ substitution ratio. Saturation magnetization and coercivity increase with increasing Ni2+ content. These results indicates that the synthesized Ni–Zn spinel ferrite nanoparticles could be used in photocatalytic and high-frequency applications with optimum Ni2+ substitution for Zn2+cations.

Sol-Gel synthesis of Ni-doped Zn-based spinel nanoferrites with structural and dielectric characterizations along with magnetic analysis

Ni-doped zinc ferrites (NixZn1−xFe2O4, 0.00 ≤ x ≤ 0.20 in steps of 0.05) were successfully synthesized using a sol-gel self-combustion method. The addition of nickel was aimed at modifying the high-frequency dielectric and magnetic properties of zinc ferrites. Various characterizations, including XRD, FTIR, LCR, and VSM analyses, were conducted to examine the crystal structure, absorption bands, dielectric properties, and magnetic properties of the compounds. XRD patterns revealed a monophasic cubic spinel structure with a preferred (311) plane orientation. The incorporation of Ni resulted in an increased crystallite size as determined by the Scherrer equation and Williamson-Hall method. The lattice parameters and unit cell volume decreased, while X-ray density increased. FTIR transmittance spectra confirmed absorption bands associated with tetrahedral and octahedral bonding. Dielectric parameters were studied across a frequency range of 1 MHz to 3 GHz, with the Maxwell-Wagner model used to explain the observations. Both components of the complex dielectric constant decreased with increasing frequency, indicating normal dispersion behavior of spinel ferrites. The electric modulus revealed relaxation mechanisms, while AC conductivity demonstrated conduction mechanisms. Magnetic properties were characterized using M-H loops measured via VSM. Increasing the Ni concentration led to higher saturation magnetization (Ms), magnetic remanence (Mr), and coercivity (Hc). Magnetic moments and anisotropy constants were calculated based on observed values of Ms and Hc. In summary, the nickel-doped zinc ferrites exhibited notable structural, magnetic, and dielectric properties, suggesting their potential utility in microwave and high-storage magnetic devices.

Crossover to the negative dielectric constant in La3+ and Dy3+ doped Co-Zn spinel nanoferrites

The paper is focused on a comprehensive study of cation distribution and impedance spectroscopy analysis of pristine and rare earth ions (La3+ and Dy3+) doped Co0.7Zn0.3Fe2O4 ferrite nanocrystals. The samples have a single phase spinel cubic structure of space group Fd3̅m with a in the range of 0.8400−0.8408 nm as confirmed by Rietveld refinement analysis of the X-ray diffraction (XRD) data. The cation distribution property of these compositions has been thoroughly studied using the data of XRD as well as Raman spectra. It is predicted that Co2+ and Zn2+ ions prefer to occupy both the sites, tetrahedral A and octahedral B, but rare earth ions have a strong preference for B-site. The non-uniform, agglomerated grains of these samples have been observed using the field emission scanning electron microscope. Up to a particular temperature, the samples have shown a positive dielectric constant, but above that, an unusual result of negative dielectric constant is observed; the Nyquist plots and other related parameters change their features in this crossover region. The doped samples have shown higher dielectric constant and lower loss as compared to the parent sample in the frequency range of 104–106 Hz and temperature interval of 25−300 °C. The variation of dielectric modulus confirms the non-Debye type relaxor behavior of the samples. Our reported results would facilitate applications of these materials for a wide range of microwave devices.

Structural and magnetic features of Pr, PrY, PrYDy doped and undoped CoNi nanospinel ferrites

Structural and magnetic features of Pr, PrY, PrYDy doped and undoped CoNi nanospinel ferrites

Effect of 16O6+ ion-irradiation on structural, magnetic properties and antistructural modeling of Zn-nanoferrites

XRD analysis and magnetic measurements were used to study the effect of 80 MeV 16O6+ ion-irradiation on structural, magnetic properties, and anti-structural modeling of as-burnt ZnFe2O4 synthesized by sol-gel auto-combustion technique. XRD confirms the formation of single-phase spinel nanoferrite. Irradiation leads to modification of (i) lattice-parameter; strain; oxygen parameter, Fe3+, Zn2+ions on A, B site; inversion degree; A-O-B, A-O-A, B–O–B super-exchange-interaction; (ii) saturation magnetization; anisotropy; squareness-ratio; surface dead-layer-thickness. Antistructural modeling describes the surface-active centers for pristine and irradiated samples. Studies reveal strong connection between structural and magnetic properties, useful for ion-irradiation-induced tuning properties of ZnFe2O4.

Experimental study on the radiation protecting ability of composites containing barium titanate and nanospinel ferrite

The search for new, non-toxic, and effective alternatives for radiation protection to lead-based materials is highly demanded in the present era. In the present research, a series of ceramic composites of barium titanate (BaTiO3, BTO) added with different amounts (x = 0, 5, 10, and 20 wt%) of nano spinel ferrite (Co0.8Ni0.1Mn0.1Fe1.9Ce0.1O4; NSF) were fabricated to evaluate their shielding performance against gamma radiation. The different samples were subjected to photons with energy ranging from 0.060 to 1.333 MeV emitted from Co-60, Cs-137, and Am-241-point sources, and the intensity of photons was detected using the HPGe detector. The prepared ceramics were first characterized by the XRD diffraction technique to examine the phase and crystal structure. The analysis showed the successful formation of the desired composites. The linear attenuation coefficient (LAC) values were determined experimentally to test the shielding performance of the composites. The LAC achieves its maximum values at an energy level of 0.06 MeV (31.88, 31.98, and 32.12 cm−1 for the composites with x = 5, 10, and 20 wt%, respectively, then it decreases at 0.662 MeV to 0.459, 0.461, and 0.465 cm−1 for the same mentioned compositions. LAC results showed that the current ceramics have a reasonably strong attenuation efficiency at low energy and can block many photons. The highest radiation protection efficiency (RPE) has occurred at 0.06 MeV and it is in the order of 95%. The RPE of the composite with x = 20 wt% is slightly greater than the RPE of the other ceramic samples. The half-value layer (HVL) data demonstrated that the shielding efficiency is related to the composition of the material, where the composite with x = 20 wt% showed a lower HVL than the other composites.

Impact of Er-Y co-doping on structure, magnetic features, and hyperfine interactions of NiCo nanospinel ferrites: Sonochemical synthesis

Impact of Er-Y co-doping on structure, magnetic features, and hyperfine interactions of NiCo nanospinel ferrites: Sonochemical synthesis

Co Doped Mg–Zn Spinel Nano-ferrites as a Sustainable Magnetic Nano-photo-catalyst with Reduced Recombination for Photo Degradation of Crystal Violet

Co Doped Mg–Zn Spinel Nano-ferrites as a Sustainable Magnetic Nano-photo-catalyst with Reduced Recombination for Photo Degradation of Crystal Violet

Effect of sonochemically synthesized Ni0.4Cu0.2Zn0.4DyxFe2-xO4 nanospinel ferrites on human colorectal carcinoma and human embryonic kidney cells

Dysprosium-substituted nickel-copper-zinc ferrite Ni0.4Cu0.2Zn0.4DyxFe2-xO4 (x ≤ 0.10) nanospinel ferrites (NSFs) (Dy-NiCuZn NSFs) were prepared by an ultrasonication assisted sol–gel chemical approach. The synthesized Dy-NiCuZn NSFs displayed a Porous Microsphere Assembly (PMA) based on Scanning Electron Microscopy (SEM) results. X-ray diffraction (XRD) results revealed the cubic spinel structures of the NSFs and their crystallite sizes ranged between 17.19 and 30.22 nm. TEM analysis revealed the presence of Dy-NiCuZn NSFs with a 15.2 nm size in diameter. BET surface analysis calculations showed that the pore size of NSFs varies between 3.0 nm and 4.0 nm. A microporous structure was confirmed in the NSFs, and their surface area generally decreased (247 to 201 m2/g) as the Dy ratio increased in the NSFs. Antiproliferative activities of NSFs were studied on HCT-116 human colorectal carcinoma cells (HCT-116) and human embryonic kidney cells. Inhibitory concentration values of NSFs were determined to lie between 145 µg/mL to 408 µg/mL for HCT-116 cells. A noteworthy reduction in cell viability after the treatments of cells with NSFs was detected. NSFs-treated cells showed nuclear disintegration and chromatic fragmentation which are signs of apoptosis or programmed cell death in human colorectal cancer cells.

Sol-gel auto-combustion developed Nd and Dy co-doped Mg nanoferrites for photocatalytic water treatment, electrocatalytic water splitting and biological applications

Sol-gel auto-combustion synthesis was considered for development of MgNd0.5xDy0.5xFe2-xO4 (x = 0.00, 0.01, 0.02, 0.03) nanoferrites to analyze the structural, optical, morphological, photocatalytic, magnetic, electrocatalytic, and antibacterial traits of nanomaterials. X-ray diffraction (XRD) patterns illustrate the existence of spinel phase for synthesised nano ferrites with no impurity phases. With increased neodymium (Nd) and dysprosium (Dy) content, the energy band gap of produced nanoferrites was decreasing from 1.73 to 1.49 eV. The magnetic characteristics indicates that with Nd and Dy doping, excellent saturation magnetization (Ms) and coercivity (Hc) in the range of 27.47–32.30 emu/g and 51.79–80.28 Oe were observed for produced nanoferrites. Electrocatalytic traits of developed nanoferrites were investigated for HER and OER in 0.5 N H2SO4 and 0.1 N KOH electrolyte using a calomel electrode as a reference electrode, respectively. According to photodegradation investigation, doped samples performed better in terms of photocatalytic efficiency under the specific conditions (catalytic dose = 0.05 g, dye concentration = 10 mg/L− and pH = 7). The prepared MgNd0.015Dy0.015Fe1.97O4 (x = 0.03) nanoferrite sample shows higher photocatalytic activity due to increased active sites and smaller band gap. Furthermore, the catalyst efficiency did not decrease significantly after the five consecutive reuse cycles. The antibacterial effects of developed Mg spinel nanoferrites for gram-positive bacteria (Staphylococcus aureus) and gram-negative bacteria (Escherichia coli) are found to be effective. Therefore, with these superior electrocatalytic, photocatalytic, and antibacterial traits, the developed Mg nano ferrites are suitable for hydrogen evolution, wastewater treatment, and biological applications.

Impact of Adsorption of Rare-Earth Elements on the Structure and Magnetic Parameters of Nanostructured Ceramic Oxides Containing Mg Nano Spinel Ferrite

This study focuses on the characterization and synthesis of ceramic materials that have magnetic nanoparticles (MgFe2O4) within an insulating (wüstite or magnesiowüstite) matrix (Mg1-xFexO). Ceramic Oxides were employed to absorb and elute rare-earth elements (REEs). Elements were carried out in experimental batches, including the effect of pH, adsorbent dose initial REE ions concentration, and equilibrium time. The Langmuir isotherm with a monolayer adsorption capacity surpassed 397 mg g−1 at room temperature. REE ions were effectively eluted from loaded Ceramic Oxides nanoparticles with 0.1 mol l−1 of HCl acid with an efficiency of 98%. Equilibrium modeling presented the Freundlich isotherm as the best fit model for both adsorbents and metal ions, indicating heterogeneity of the surface binding sites during adsorption. The pseudo-first order kinetic model was the best-fit model. Different qualitative techniques are used to emphasis the adsorption of REE ions onto Ceramic Oxides nanoparticles. The effect of REEs ions adsorption on the structural and morphological properties have been investigated using X-ray diffraction (XRD), porosity & surface area scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDX). The functional groups were detected by Fourier Transform infrared spectroscopy (FTIR). By applying a magnetic field of ±20 kOe, using vibrating sample magnetometer (VSM), (M-H) hysteresis loops were formed. The difference in ionic radius and atomic weight of the REE ions is highly renovated to the fluctuations in crystallographic and magnetic parameters. Finally, Ceramic Oxides nanoparticles possessed good adsorption properties such as stability and reusability, which have potential application in wastewater treatment.

Structural, morphological and magnetic properties of (Ni0.5Co0.5)[Ga Gd Fe2–2]O4 nanoparticles prepared via sonochemical approach

In this report, the impact of Ga3+ and Gd3+ co-substitution on different types of behavior of Ni-Co nanospinel ferrites (NSFs), (Ni0.5Co0.5)[GaxGdxFe2–2x]O4 (0.000 ≤ x ≤ 0.025), was investigated. NSFs were fabricated through ultrasound irradiation. The structure, composition, and spherical morphology of all products were verified by numerous characterization techniques such as X-ray diffraction (XRD), scanning and transmission electron microscopes (SEM & TEM), and selected area electron diffraction (SAED). Mossbauer spectra are composed of two ferromagnetic sextets and one paramagnetic doublet. These spectra were fitted to extract hyperfine parameters of the doped samples. Both sublattices' hyperfine magnetic field decreases with substitution. The isomer shift values show that the Mossbauer spectra are composed of magnetic Fe3+ sextets. The magnetization measurements at variable magnetic field (M-H) were investigated via a vibrating sample magnetometer (VSM) at a variable magnetic field (M-H) at temperatures (T) from 300 and 10 K. All NSFs disclose ferrimagnetic behavior at both 300 and 10 K where they are soft and hard, respectively. We determine that the remanence magnetization (Mr), saturation magnetization (Ms), and magneton number (nB) decrease with increasing Ga3+ and Gd3+ ions contents. The reduction in these values was predominantly recognized to the impact of cation redistribution and surface spins on tetrahedral (Td) and octahedral (Oh) sites. As the Ga3+ and Gd3+ contents increase, the coercivity (Hc) is also found to decrease.

Structural, dielectric, and thermal properties of Zn and Cr doped Mg- Co spinel nanoferrites

Nanoferrites play a pivotal role in resolving worldwide electronic and microwave devices. Spinel ferrites have exceptional structural, morphological, and dielectric properties. The composition Zn 0.5–xMg0.25+x Co 0.25Cr1–x Fe 1+x O 4 (ZMCCF) where x varies from 0–0.5 with the difference of 0.25 was synthesized via auto combustion (sol-gel) route. The structural, thermal, and dielectric characterizations were done to observe the responses of variation of x in designed nanoferrites. The designed nanoferrites with a variation of x experienced a promising change in structural, thermal, and dielectric responses. Based on Koop’s theory, the dielectric constant decreases with the increase in frequency, which is the favorable trend of spinel ferrites. The different cationic distributions in the spinel structure endorse this behavior. The maximum value of the tangent loss at low frequencies reflects the application of these materials in medium-frequency devices. Therefore, planned spinel nanoferrites may benefit advanced electronics and microwave devices.

Ce-Co-Mn-Zn ferrite nano catalyst: A synergetic effect of rare earth Ce3+ on enhanced optical properties and photocatalysis

Photocatalysis in spinel nanoferrites offers various applications in the remediation of environmental challenges. A novel spinel Co0.5Mn0.25Zn0.25CexFe2-xO4 (CMZCF0-CMZCF5) nanoferrite photocatalysts were prepared by a combustion approach for the methylene blue (MB) dye degradation. All the CMZCF nanoferrites were characterized via XRD, FTIR, XPS, DRS, and photon driven catalysis for MB dye degradation. Williamson- Hall approach was utilized to determine the CMZCF nanoferrites crystallite size, which was found in the span of 20.88–25.07 nm. The XPS peaks reflect the chemical composition of the CMZCF nanoferrites, and their intensities qualitatively reflect their elemental concentration ratio. The band gap energies of the CMZCF nanoferrites were smaller than that of the pure ferrite devoid of Ce, hence enhancing their photocatalytic efficacy. The energy gap of the nanoferrite CMZCF5 was decreased with an enhancing ratio of 5.16% than the pristine one. The maximum percentage of MB removal was 97.01% for CMZCF5 compared with 9.80% for MB removal alone, during 60 min under solar light. Incorporating Ce cations significantly reduces the electron-hole pairs recombination and dramatically increases the material's ability to absorb visible light. The degradation efficiency of CMZCF5 across five cycles is 97.01, 96.74, 96.43, 96.21, and 95.63%, representing their stability and efficiency. The nano-photocatalytic CMZCF5 was shown to be a promising material for the treatment of wastewater contaminated by MB pollutants.

Visible light induced photocatalytic degradation of methylene blue dye by using Mg doped Co-Zn nanoferrites

Spinel nanoferrites are used by researchers in past years in various fields of applications like high-frequency applications, electronics, microwave devices and as a photocatalyst. Being very porous and having a low specific surface area, these nanomaterials are here used for the degradation of methylene blue dye using a heterogeneous adsorption photocatalytic process. Mg2+ substituted Co-Zn nano ferrite particles with composition Co0.5Zn0.5MgxFe2-xO4, where x = 0.25–1.0 with a step size of 0.25, were prepared using a chemical route named citrate precursor technique and various characterization of the samples was performed using Scanning electron microscopy (SEM), X-ray powder diffractometry (XRD), UV visible spectroscopy, Fourier infrared spectroscopy technique (FT-IR) for investigating the structural and optical properties. XRD spectra showed reflection peaks indexed to (220), (222), (400), (422), (511) and (440) dictating the cubic structure of the nanoferrite samples and one characteristic peak at (311) corresponding to the single-phase spinel cubic structure of the synthesized nanoferrite material. The materials were found to have good magnetic properties with saturation magnetization in the range 52.15 to 28.24 emu/g. A visible light source was used to degrade the methylene blue (MB) dye from water using a photocatalytic mechanism by creating a Fenton-type system. Almost complete degradation of MB dye was observed in one hour of visible light irradiation for Mg2+ concentration x = 1.0. Also, the degradation process of dye was found to have a pseudo first order kinetics model for all the synthesized samples. Hence, it can be confirmed that Mg substituted Co-Zn nanoferrites can act as an efficient catalyst for water purification by photocatalytic mechanism without any harm to the environment.

Intrinsic magnetic-optical features of Dy3+ ion substituted NiCuZn nanospinel ferrites via sonochemical approach

Ni0·4Cu0·2Zn0.4DyxFe2-xO4 (x ≤ 0.10) (NCZDy) nanospinel ferrites (NSFs) were prepared by an ultrasonication approach assisted sol-gel synthesis methodology. The cubic spinel structures of products were verified by XRD (X-ray powder diffraction) study. Intrinsic vibrational absorption bands of nanoparticles for their octahedral band (υ2) at 417 cm−1 and tetrahedral (υ1) band at 563-580 cm−1 were detected by FT-IR (Fourier-transform infrared) analysis. Magnetic studies by VSM (Vibrating sample magnetometry) confirmed the soft ferromagnetic nature of all products at 15 K and 300 K temperatures. As the amount of Dy3+ rises, saturation and remanent magnetization (Ms and Mr) values first increase for x = 0.02 composition; then they start to decrease with further rising the Dy3+ content. FC (Field-cooled) and ZFC (zero field-cooled) magnetization studies reveal that the irreversible temperature is above 300 K and the samples display spin glass behavior. Mössbauer spectra (MOS) were acquired to calculate hyperfine parameters by room-temperature (RT) spectra fitting and results indicated Dy3+ ions occupy octahedral sites. The optical investigation showed NCZDy (x ≤ 0.10) NSFs carry out a direct band character, and band gap values lay between 1.69 and 2.33 eV. All samples absorb the light within the visible region which is evident from the % Diffuse Reflectance Spectroscopy (DRS) results.

Effects of Pr3+ ion doping on magnetic features of Ni–Co nanospinel ferrites synthesized via sonochemical approach

The praseodymium ion (Pr3+) substituted Ni0.5Co0.5Fe2O4 nanospinel ferrites, (Co0.5Ni0.5PrxFe2-xO4 (Pr → CoNi) (x ≤ 0.10) NSFs), were synthesized via sonochemical route. XRD confirmed the single cubic structure of all samples with the crystallite size within the range of 9–11 nm.The morphology of (Pr → CoNi) (x ≤ 0.10) NSFs) particles was analyzed by SEM and TEM and showed the spherical shape. Mossbauer study showed that the larger Pr3+ ions prefer the B site. According to the magnetic study, the superparamagnetic character increased with increase of Pr3+ions. The magnetic characteristics are elucidated through both hysteresis curves and temperature (T) dependence of magnetization (M). Magnetization (M) vs external field (H) hysteresis curves were performed at both 300 (RT) and 10 K. It is revealed that Pr → CoNi NSFs exhibit superparamagnetic (SPM) nature performed at RT. Saturation magnetization (Ms), magnetic moment (nB), squareness ratio (SQR), remanence (Mr), and coercivity (Hc) were determined. The Hc of Pr → CoNi (x ≤ 0.10) NSFs was found to be larger than that of the host material. On the other hand, at both temperatures, the magnetization data demonstrates the crucial impact of Pr3+ ions which diminish the Ms, Mr and nB of the host material. The magnetic parameters for Pr → CoNi (x ≤ 0.10) NSFs barely fluctuate and depend on the cation distribution. At 10 K, the SQR of all samples is calculated to be ∼ 0.5 which reflects the uniaxial symmetry and a single-domain structure formation. For Pr → CoNi (x ≤ 0.10) NSFs, much lower SQR values are attained at room temperature (RT), indicating a decrease in the exchange interaction, and suggesting a multi-domain wall structure. For Pr → CoNi (x ≤ 0.10) NSFs, the M values through field-cooling (FC) curves exhibit a slight decrease with increasing T. Their zero field-cooling (ZFC) curves display a nonmonotonic decrease with the decreasing T and result in a low magnetization at low Ts. ZFC and FC curves of Pr → CoNi (x ≤ 0.10) NSFs indicate a large irreversibility.

Influence of Tm and Tb co-substitution on structural and magnetic features of CoFe[formula omitted]O[formula omitted] nanospinel ferrites

Tm-Tb co-substituted CoFe 2O4 nanospinel ferrites (CoTm xTbxFe2−2xO4, CoTmTb (x = 0.00– 0.03) NSFs)) were prepared via a sonochemical chemical route. The microstructures and morphologies of the NSFs were investigated via XRD, SAED and TEM/SEM, along with EDX techniques. The XRD analysis confirmed the cubic structure all the products along with the absence of any impurities. All the crystallite sizes were observed to be within the range of 9–11 nm. Electron microscopy techniques (SEM, TEM and HR-TEM) proved a cubic morphology in each case and their chemical compositions were confirmed by EDX. The magnetic properties of the synthesized NSFs were investigated via VSM through analysis of the magnetization versus applied magnetic field data. The M–H studies were made at 10 and 300 K. All the NSFs displayed soft ferrimagnetic behavior. It was observed that Tb3+ and Tm3+ ions substitutions provoke substantial variations in the magnetic behavior of the host CoFe 2O4 system. Upon doping the CoFe 2O4 system with the Tb3+ and Tm3+ ions, the magnetic features, Ms (saturation) and Mr (remanent) as well as the Hc (coercive field), increased for x=0.010 and then started to decrease gradually with a further increase in the dopant contents (Tb3+ and Tm3+ ions). The exchange interactions between the cations distributed over the A and B sites is one of the main reasons for the observed evolution in the magnetization magnitudes with the composition. Other factors, like strain, surface spins disorder, crystallite size, size of magnetic domains and Bohr magneton number, were also reported in order to explain the variations in diverse magnetic parameters.

Structural and magnetic analysis of Cd-Zn spinel ferrite nanoparticles

Sol-gel auto-combustion synthesis technique was employed to synthesize Cd-Zn ferrite nanoparticles with composition Zn1-xCdxFe2O4, where 0.0 ≤ x ≤ 1.0. The physical properties of prepared samples were inspected by using x-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR) and vibration sample magnetometer (VSM) techniques. XRD analysis confirmed the formation of Cd-Zn spinel nanoferrites with an increase in experimental lattice constant from 8.37 Å to 8.74 Å for zinc and cadmium ferrite samples, respectively. Variation of tetrahedral and octahedral hopping lengths, crystallite size, microstrain and dislocation density with Cd-content has been investigated and elucidated. SEM micrographs showed agglomeration of nearly-spherical grains that increased in size with Cd-content increase. FTIR analysis confirmed the existence of the characteristic tetrahedral and octahedral stretching vibrations of metal ion and oxygen complex in the range 429–558 cm−1. VSM measurements revealed a tuning in coercivity to higher values and a decrease in saturation magnetization as Cd-content increased. The calculated cations distribution, bond lengths, bond angles and interionic distances between cations at tetrahedral and octahedral sites attribute the observed decrease in saturation magnetization to weak interaction between cations in the two sites.

Lanthanide loaded dopamine modified spinel nanoferrites: Novel photocatalyst with enhanced catalytic activity

Lanthanide loaded dopamine modified spinel nanoferrites: Novel photocatalyst with enhanced catalytic activity