Ni0.4Cu0.2Zn0.4TbxFe2-xO4 nanospinel ferrites: Ultrasonic synthesis and physical properties

Unveiling the impact of Ni2+/Y3+ co-substitution on the structural, dielectric, and impedance properties of multiferroic spinel ferrite for hydroelectric cell application

Substitution with rare earth (RE3+) and transition (X = Cu, Ni, Mn, Zn, etc.) metals can distort the spinel ferrite structure and create defects, which can be exploited in multifarious applications. In this study, yttrium and nickel co-substituted cobalt ferrites [Co1-xNixFe1.85Y0.15O4], (0.0 ≤ x ≤ 0.15) were synthesized by a modified sol-gel reaction route. The X-ray diffraction (XRD) patterns confirmed the single phase and highly crystalline nature of the prepared samples. Field emission scanning electron microscopy with energy dispersive X-ray (FESEM-EDX) spectroscopy confirmed the morphology of the prepared samples sintered at 800 °C and showed the grain sizes of the particles decreased with the addition of nickel ions. The simultaneous co-existence of saturation magnetization and ferroelectricity at room temperature confirmed the multiferroic nature of the co-substituted cobalt ferrites. The dielectric and impedance studies confirmed the Maxwell-Wagner polarization phenomenon and the enhanced values with Y-Ni co-substitution. The maximum saturation ferroelectric polarization was attained around 6.142 μC cm-2 for yttrium-substituted cobalt ferrite and then decreased with the increase in the substitution % of nickel. The maximum value of saturation magnetization (Ms = 99.50 emu g-1) was obtained with the highest substitution % of nickel of x = 0.15 in yttrium-substituted cobalt ferrite (YCFO) nanoferrites, which was also confirmed from the vibrating sample magnitude (VSM) studies at room temperature. The improvements in the structural, morphological, electrical, and multiferroic properties in the co-substituted cobalt ferrites were found to correlated to the substitution of the bigger cationic Y3+ ions compared to the Fe3+ ions, while the small substitution of Ni2+ ions lead to changes in the lattice parameters, porosity, and conduction behavior. These significant enhancements in co-substituted cobalt ferrites can be exploited for hydroelectric cell applications.

Review on magnetic spinel ferrite (MFe2O4) nanoparticles: From synthesis to application

Magnetic spinel ferrite materials offer various applications in biomedical, water treatment, and industrial electronic devices, which has sparked a lot of attention. This review focuses on the synthesis, characterization, and applications of spinel ferrites in a variety of fields, particularly spinel ferrites with doping. Spinel ferrites nanoparticles doped with the elements have remarkable electrical and magnetic properties, allowing them to be used in a wide range of applications such as magnetic fields, microwave absorbers, and biomedicine. Furthermore, the physical properties of spinel ferrites can be modified by substituting metallic atoms, resulting in improved performance. The most recent and noteworthy applications of magnetic ferrite nanoparticles are reviewed and discussed in this review. This review goes over the synthesis, doping and applications of different types of metal ferrite nanoparticles, as well as views on how to choose the appropriate magnetic ferrites based on the intended application.

Adsorption kinetics for the removal of toxic Congo red dye by polyaniline and citrus leaves as effective adsorbents

This study focusses on the synthesis of polyaniline (PANI) and polyaniline base adsorbent utilizing Citrus limon leaves (CL) powder. The polyaniline base adsorbent with C. limon was synthesized using the same process as polyaniline synthesis, but with the addition of leaves powder. PANI and PANI based adsorbent with C. limon leaves powder (PANI/CL) were characterized by Fourier Transform Infra-Red (FTIR), UV-Visible spectroscopy and Scanning Electron Microscopy (SEM). This synthesized material was employed for the removal of congo red (CR) dye from industrial wastewater. Furthermore, the Langmuir, Temkin and Freundlich isotherms were also applied to evaluate experimental results. PANI is an efficient adsorbent for CR removal with 71.9 mg/g, while PANI/CL is an efficient adsorbent with 80 mg/g removal of dye according to a comparison of maximal adsorption capabilities. The data concludes that the prepared adsorbents could possibly be employed for the removal of toxic dyes from industrial effluents at large scale and ultimately could help in improving the environment.

Microwave assisted green synthesis of ZnO nanoparticles using Rumex dentatus leaf extract: photocatalytic and antibacterial potential evaluation

In the present study, biological method was opted to synthesize ZnO NPs from Rumex dentatus plant. 0.1 M solution of zinc nitrate hexahydrate is mixed with the aqueous solution of R. dentatus plant leaves extract. The proportion of each solution was 1:1. Extract of plant leaves act as reducing agent. Firstly, the color changed from dark green to brown was observed and precipitates of light brown color appeared. Characterization of produced ZnO NPs was done using UV–Visible spectroscopy, scanning electron microscopy (SEM), energy dispersive X-rays (EDX) and X-ray diffraction (XRD) spectroscopy. The prepared ZnO NPS shows maximum absorption at 373 nm, in UV–Visible range. The shape of synthesized ZnO NPs is displayed by SEM. XRD analysis explains the average size of NPs is 6.19 nm. EDX tells about the percentage composition of synthesized ZnO NPs. Antibacterial analysis declared the NPs as good antibacterial agents. Photocatalytic activity of ZnO NPs was done using methyl orange dye. It was concluded that ZnO NPs can degrade toxic pollutants especially dyes.

New TiO2-doped Cu-Mg spinel-ferrite-based photocatalyst for degrading highly toxic rhodamine B dye in wastewater

The quest for finding an effective photocatalyst for environmental remediation and treatment strategies is attracting considerable attentions from scientists. In this study, a new hybrid material, Cu_0.5Mg_0.5Fe₂O₄-TiO₂, was designed and fabricated using coprecipitation and sol-gel approaches for degrading organic dyes in wastewater. The prepared hybrid materials were fully characterized using scanning electron microscopy, X-ray diffraction, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy. The results revealed that the Cu_0.5Mg_0.5Fe₂O₄-TiO₂ hybrid material was successfully synthesized with average particle sizes of 40.09 nm for TiO₂ and 27.9 nm for Cu_0.5Mg_0.5Fe₂O₄. As the calculated bandgap energy of the hybrid material was approximately 2.86 eV, it could harvest photon energy in the visible region. Results indicate that the Cu_0.5Mg_0.5Fe₂O₄-TiO₂ also had reasonable magnetic properties with a saturation magnetization value of 11.2 emu/g, which is a level of making easy separation from the solution by an external magnet. The resultant Cu_0.5Mg_0.5Fe₂O₄-TiO₂ hybrid material revealed better photocatalytic performance for rhodamine B dye (consistent removal rate in the 13.96 × 10^-3 min^-1) compared with free-standing Cu_0.5Mg_0.5Fe₂O₄ and TiO₂ materials. The recyclability and photocatalytic mechanism of Cu_0.5Mg_0.5Fe₂O₄-TiO₂ are also well discussed.

Influence of size polydispersity on magnetic field tunable structures in magnetic nanofluids containing superparamagnetic nanoparticles

We probe the influence of particle size polydispersity on field-induced structures and structural transitions in magnetic fluids (ferrofluids) using phase contrast optical microscopy, light scattering and Brownian dynamics simulations. Three different ferrofluids containing superparamagnetic nanoparticles of different polydispersity indices (PDIs) are used. In a ferrofluid with a high PDI (∼0.79), thin chains, thick chains, and sheets are formed on increasing the in-plane magnetic field, whereas isotropic bubbles, and hexagonal and lamellar/stripe structures are formed on increasing the out-of-plane magnetic field over the same range. In contrast, no field-induced aggregates are seen in the sample with low polydispersity under the above conditions. In a polydisperse sample, bubbles are formed at a very low magnetic field strength of 30 G. Insights into the structural evolution with increasing magnetic field strength are obtained by carrying out Brownian dynamics simulations. The crossovers from isotropic, through hexagonal columnar, to lamellar/stripe structures observed with increasing field strength in the high-polydispersity sample indicate the prominent roles of large, more strongly interacting particles in structural transitions in ferrofluids. Based on the observed microstructures, a phase diagram is constructed. Our work opens up new opportunities to develop optical devices and access diverse structures by tuning size polydispersity.

Al-Suhaimi E, Hussain M, Yousuf Bari M, Mehmood Ali S, Al-Jameel SS, Slimani Y, Khan FA, Baykal A. Ultrasonic Synthesis and Biomedical Application of Mn0.5Zn0.5ErxYxFe2-2xO4 Nanoparticles

In the present study, biocompatible manganese nanoparticles have been linked with zinc and iron molecules to prepare different derivatives of Mn_0.5Zn_0.5Er_xY_xFe_2-2xO₄ NPs (x = 0.02, 0.04, 0.06, 0.08, 0.10), using an ultrasonication approach. The structure, surface morphology, and chemical compositions of Mn_0.5Zn_0.5Er_xY_xFe_2-2xO₄ NPs were elucidated by X-ray diffractometer (XRD), High-resolution transmission electron microscopy (HR-TEM), scanning electron microscope (SEM), and Energy Dispersive X-Ray Analysis (EDX) techniques. The bioactivity of Mn_0.5Zn_0.5Er_xY_xFe_2-2xO₄ NPs on normal (HEK-293) and (HCT-116) colon cancer cell line was evaluated. The Mn_0.5Zn_0.5Er_xY_xFe_2-2xO₄ NPs treatment post 48 h resulted in a significant reduction in cells (via MTT assay, having an IC₅₀ value between 0.88 µg/mL and 2.40 µg/mL). The specificity of Mn_0.5Zn_0.5Er_xY_xFe_2-2xO₄ NPs were studied by treating them on normal cells line (HEK-293). The results showed that Mn_0.5Zn_0.5Er_xY_xFe_2-2xO₄ NPs did not incur any effect on HEK-293, which suggests that Mn_0.5Zn_0.5Er_xY_xFe_2-2xO₄ NPs selectively targeted the colon cancerous cells. Using Candida albicans, antifungal activity was also studied by evaluating minimum inhibitory/fungicidal concentration (MIC/MFC) and the effect of nanomaterial on the germ tube formation, which exhibited that NPs significantly inhibited the growth and germ tube formation. The obtained results hold the potential to design nanoparticles that lead to efficient bioactivity.

Effect of reaction condition on microstructure and properties of (NiCuZn)Fe2O4 nanoparticles synthesized via co-precipitation with ultrasonic irradiation

Nano-spinel ferrites synthesized via chemical co-precipitation method are small in size and have serious agglomeration phenomenon, which makes separation difficult in the subsequent process. Ni0.4Cu0.2Zn0.4Fe2O4 ferrites nanoparticles were synthesized via co-precipitation assisted with ultrasonic irradiation produced by ultrasonic cleaner with 20 kHz frequency using chlorinated salts and KOH as initial materials. The effects of ultrasonic power (0, 40 W, 60 W, 80 W) and reaction temperature on the microstructure and magnetic properties of ferrite nanoparticles were investigated. The structure analyses via XRD revealed the successful formation of pure (NiCuZn)Fe2O4 ferrites nanospinel without any impurity. The crystallites sizes were less than 40 nm and the lattice constant was near 8.39 Å. The TEM showed ferrite particle polygonal. M-H analyses performed the saturation magnetization and coercivity of ferrite nanoparticles obtained at the reaction temperature of 25℃ were higher than at 50℃ with same power. The samples exhibited the highest values of Ms 55.67 emu/g at 25℃ and 47.77 emu/g at 50℃ for 60 W and the lowest values of Hc 71.23 Oe at 25℃ for 40 W and 52.85 Oe at 50℃ for 60 W. The squareness ratio (SQR) were found to be lower than 0.5, which revealed the single magnetic domain nature (NiCuZn)Fe2O4 nanoparticles. All the outcomes show the ultrasonic irradiation has positive effects on improving the microstructure and increasing magnetic properties.

Sonochemical catalysis as a unique strategy for the fabrication of nano-/micro-structured inorganics

Ultrasound-assisted approaches, as an important trend in material synthesis, have emerged for designing and creating nano-/micro-structures. This review simply presents the basic principles of ultrasound irradiation including acoustic cavitation, sonochemical effects, physical and/or mechanical effects, and on the basis of the latest progress, it newly summarizes sonochemical catalysis for the fabrication of nano-structured or micro-structured inorganic materials such as metals, alloys, metal compounds, non-metal materials, and inorganic composites, where the theories or mechanisms of catalytic synthetic routes, and the morphologies, structures, sizes, properties and applications of products are described in detail. In the review, a few technological potentials and probable challenges of sonochemical catalysis are also highlighted for the future advance of synthesis methods. Therefore, sonochemical catalysis or ultrasound-assisted synthesis will serve as a unique strategy to reveal its great significance in material fabrication.

Impact of Tm3+ and Tb3+ Rare Earth Cations Substitution on the Structure and Magnetic Parameters of Co-Ni Nanospinel Ferrite

Tm-Tb co-substituted Co-Ni nanospinel ferrites (NSFs) as (Co0.5Ni0.5) [TmxTbxFe2-2x]O4 (x = 0.00-0.05) NSFs were attained via the ultrasound irradiation technique. The phase identification and morphologies of the NSFs were explored using X-rays diffraction (XRD), selected area electron diffraction (SAED), and transmission and scanning electronic microscopes (TEM and SEM). The magnetization measurements against the applied magnetic field (M-H) were made at 300 and 10 K with a vibrating sample magnetometer (VSM). The various prepared nanoparticles revealed a ferrimagnetic character at both 300 and 10 K. The saturation magnetization (Ms), the remanence (Mr), and magneton number (nB) were found to decrease upon the Tb-Tm substitution effect. On the other hand, the coercivity (Hc) was found to diminish with increasing x up to 0.03 and then begins to increase with further rising Tb-Tm content. The Hc values are in the range of 346.7-441.7 Oe at 300 K to 4044.4-5378.7 Oe at 10 K. The variations in magnetic parameters were described based on redistribution of cations, crystallites and/or grains size, canting effects, surface spins effects, super-exchange interaction strength, etc. The observed magnetic results indicated that the synthesized (Co0.5Ni0.5)[TmxTbxFe2-x]O4 NSFs could be considered as promising candidates to be used for room temperature magnetic applications and magnetic recording media.