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The mixed zinc-ferrite spinel magnetic nanoparticles (MNPs) with the general formula ZnxFe3−xO4 are among the most extensively studied families of Fe oxides due to their interesting and diverse chemical, electronic, and magnetic properties. These systems offer the possibility of surface functionalization and possess high biocompatibility, making them highly attractive for applications in biomedicine, such as magnetic fluid hyperthermia (MFH). The efficiency of the MFH process relies on the magnetic, structural and morphological properties of the MNPs. The substitution with the Zn ion and the cationic distribution, as well as the synthesis process employed, have a direct impact on the final properties of these oxides. Therefore, it is essential to have tools that enable a comprehensive characterization of the system to assess its performance in MFH. In this study, we have synthesized four ZnxFe3−xO4 MNP systems using three different methods: two by thermal decomposition at high temperatures, one by co-precipitation, and another by co-precipitation followed by ball milling. We analyze the effect of these various synthesis processes on the magnetic and crystallographic properties, aiming to correlate them with the response of each system in MFH. Neutron diffraction data are employed to determine the cation site occupation and to investigate the correlation with the synthesis method. MFH measurements were conducted in media of diverse viscosities, revealing different values of specific loss power, thus demonstrating a clear dependence on the synthesis process and Zn content. [ABSTRACT FROM AUTHOR]

This study focuses on the synthesis of nickel-substituted zinc ferrite nanoparticles, Z n 1 − x N i x F e 2 O 4 , via the sol-gel method and examines how nickel substitution influences their structural, magnetic, and optical properties. The lattice constant of the nanoparticles, which varied from 8.4296 Å to 8.4212 Å, decreased as the nickel concentration increased. Scanning electron microscopy (SEM) was employed to examine the morphology, revealing grain sizes between 46 and 53 nm, while energy dispersive X-ray spectroscopy (EDX) confirmed the elemental composition, showing nearly spherical nanoparticles containing all the constituent elements. The magnetic properties were analyzed using a vibrating sample magnetometer (VSM), which highlighted significant differences between the theoretical and experimental magnetic moments, indicating the presence of Yafet-Kittel magnetic ordering in the system. The saturation magnetization was enhanced by N i + 2 ions, reaching a maximum value of 23.864 emu/g. This enhancement makes the nickel-substituted zinc ferrite nanoparticles suitable for applications in data recording media and magnetic resonance imaging. Additionally, the values of the magnetic crystalline anisotropy constant, initial permeability, effective anisotropy constant, and anisotropic field of the synthesized samples were estimated. The optical properties of the synthesized samples were evaluated using UV–visible spectroscopy, and the band gap was determined through diffuse reflectance spectroscopy (DRS). The optical bandgap of pure zinc ferrite was measured to be 2.26 eV, and it decreased with increasing nickel concentration in the nanoparticles. [ABSTRACT FROM AUTHOR]

The world is now facing a water scarcity crisis due to waste, pollution, and uneven distribution of freshwater resources, which are limited. Thus, the creation of innovative, economical, and effective methods for purifying water is crucial. Here, the photo-assisted degradation of methylene blue (MB) dye under visible light and UV was achieved by using RGO photocatalyst loaded with Zn0.5Cu0.5Fe2O4 in three different loaded 10%, 20%, and 30% called MRGO 10, MRGO 20, and MRGO 30. Furthermore, all prepared samples was characterized by X-ray diffraction (XRD), fourier transformation infrared (FTIR), transmission electron microscope (TEM), vibrating sample magnetometer (VSM) and Raman analysis. After 40 min, the high photocatalytic efficacy effectively eliminated about 95.2% of the 10 ppm MB using 20 mg of MRGO 20 NPs at pH9 Visible light. From the results, the photocatalytic activity of MRGO 20 reduced to 54.6% after five cycles of methylene blue (MB) dye degradation. The produced samples' observed efficacy in both UV and visible light may encourage continued research into more effective photocatalysts for the filtration of water. [ABSTRACT FROM AUTHOR]

Spinel ferrites have attracted considerable interest in energy storage systems due to their unique magnetic, electrical and catalytic properties. However, they suffer from poor electronic conductivity and low specific capacity. We have addressed this limitation by synthesizing composite hollow carbon nanofibers (HCNF) embedded with nanostructured Nickel Zinc Ferrite (NZF) and Multiwalled carbon nanotubes (CNT), through coaxial electrospinning. These ternary composite nanofibers NZF‐CNT‐HCNF have a high specific capacity of 833 C g−1 at a current density of 1 A g−1 and have a capacity retention of 90 % after 3000 cycles. Their performance is much better than pure NZF fibers (180 C g−1) or hollow carbon nanofibers (96 C g−1), suggesting synergy between various constituents of the composite. A symmetric supercapacitor fabricated from NZF‐CNT‐HCNF composite nanofibers (30 % NZF) has a high specific capacity of 302 C g−1 (302 A g−1) at a current density of 1 A g−1 and has a capacity retention of 95 % after 5000 cycles. At the same current density, the device has a high energy density of 39 Whkg−1 and power density of 1000 Wkg−1 at a current density of 1 A g−1. This performance can be attributed to the high specific surface area (776 m2 g−1), mesoporosity (pore size ~4 nm), interconnectedness of the nanofibers and high electrical conductivity of CNTs. These fibers can be used as light‐weight high performance electrode materials in advanced energy storage devices. [ABSTRACT FROM AUTHOR]

Magnetic green adsorbents have been gaining importance in wastewater treatment field due to their versatile properties. In this study, a novel magnetic green adsorbent Zinc Ferrite-Rice Husk Silica (ZFN-RHS) composite has been prepared by extracting silica from rice husk. ZFN-RHS is characterised using variety of techniques which includes FESEM, FT-IR, XRD, BET, pHzpc and EDS. Effect of various parameters like time, concentration, pH, adsorbent amount and temperature was assessed using the batch adsorption method to remove cationic dyes (Methylene Blue and Crystal Violet) from aqueous solution in single as well binary dye solutions. Results showed that Lagergren pseudo-second order kinetic model best fitted with the adsorption data indicating chemisorption. In adsorption isotherm study, Freundlich as well as Langmuir adsorption isotherms fitted better than other isotherms. Maximum adsorption capacities for removal of CV and MB dyes in this study have been found to be 138.8 and 84.8 mg/g respectively. From the positive values of ΔH°, it has been observed that the process of removal of MB and CV from aqueous solution using ZFN-RHS was endothermic in nature and the negative ΔG° values confirmed the spontaneous nature of the process. Regeneration studies were also conducted with significant outcomes in five cycles. The research study revealed that ZFN-RHS can be used as an adsorbent to remove other cationic dyes also. [ABSTRACT FROM AUTHOR]

Currently, there is a rush to develop green polymeric films such as biodegradable chitosan (CH) films to control and prevent plastic pollution from degrading the environment. This study reports a novel and sustainable green approach to the development of CH films using lemon juice (LJ) and lemon peel extract (LPE), the latter to dilute the LJ. The LPE was also utilized for the synthesis of ZnFe2O4 nanoparticles (NPs), adding to this work's novelty. The crystalline size of the ZnFe2O4 NPs was computed to be ~16 nm. The introduction of 1% and 2% ZnFe2O4 NPs improved not only the mechanical properties of the films, but also their barrier properties and water solubility (WS). The tensile strength increased from 0.641 MPa to 0.835 MPa when 2% NPs were incorporated, which is almost 1.30 times greater; the NPs also enhanced the surface strength by 2.66 times, which was demonstrated by the puncture strength. The introduction of NPs occupied the vacant spaces and improved the barrier capabilities of the CH film by reducing the water vapor permeability (WVP) value from 8.752 ± 0.015 for bare CH films to 6.299 ± 0.009 for 2% NP-containing CH films. Overall, the introduction of ZnFe2O4 NPs boosted the mechanical and barrier properties of the CH films, and offers a promising method for developing sustainable, eco-friendly, and biodegradable polymeric films for potential packaging and medical applications to contribute to circular economic efforts. [ABSTRACT FROM AUTHOR]

A trend has been established concerning the research and development of various green and biodegradable plastics for multi-purpose applications, aiming to replace petroleum-based plastics. Herein, we report the synthesis of chitosan (CH) films using lemon juice; these were reinforced with NiZnFe2O4 nanoparticles (NiZnFe2O4 NPs) to obtain improved mechanical and barrier properties, facilitating their future application as sustainable, corrosion-resistant coatings for medical instruments. The synthesized NiZnFe2O4 NPs had a crystallite size of ~29 nm. Reinforcement with the nanoparticles in bio-sourced chitosan films was conducted at two concentrations: 1% and 2%. The mechanical strength of the CH film was found to be 1.52 MPa, while the 2% NiZnFe2O4 NP-containing films showed stress-bearing potential of 1.04 MPa with a larger strain value, confirming the elastic nature of the films. Furthermore, the % elongation was directly proportional to the NP concentration, with the highest value of 36.833% obtained for the 2% NP-containing films. The CH films presented improved barrier properties with the introduction of the NiZnFe2O4 NPs, making them promising candidates for coatings in medical instruments; this could protect such instruments from corrosion under controlled conditions. This approach not only broadens the application range of biopolymeric films but also aligns with global sustainability goals, serving to reduce the reliance on non-renewable corrosion-resistant coatings. [ABSTRACT FROM AUTHOR]

In this study, novel dual wave-absorbing ZnFe 2 O 4 /CNTs nanoparticles were successfully fabricated using a microwave hydrothermal method and applied for enhanced microwave-induced catalytic degradation of bisphenol A (BPA) in aqueous solution. The effects of various process parameters, including Fe3+ concentration (mass ratio of ZnFe 2 O 4 to CNTs), MW irradiation time, MW power, initial BPA concentration, and catalyst dose on the degradation process were thoroughly assessed. The results indicate that ZnFe 2 O 4 /CNTs nanoparticles effectively utilize MW energy to generate more hot spots and exhibit superior MW catalytic activity at a 1.0:10.0 mass ratio (ZnFe 2 O 4 :CNTs), due to the synergistic effect between ZnFe 2 O 4 nanoparticles and CNTs under MW irradiation. Additionally, hydroxyl radicals (·OH) play a major role in the degradation process, while superoxide radicals (·O 2 −) and holes (h+) play relatively minor roles. Potential intermediates and degradation pathways in the ZnFe 2 O 4 /CNTs/MW system have also been identified. Thus, the integrated ZnFe 2 O 4 /CNTs/MW technology shows great promise for treating environmental endocrine disruptors (EEDs) in water and wastewater. [ABSTRACT FROM AUTHOR]

Cubic spinel ferrites have developed significant attention in materials science owing to their distinctive characteristics and diverse applications. The present review emphasizes on the cubic spinel ferrites fabricated via green synthesis routes focusing on their structural characteristics and their influence on the potential biomedical applications. Various green synthesis approaches, including sol-gel, hydrothermal, microwave irradiated, microorganism and plant-mediated methods, are discussed in detail, highlighting their eco-friendly approach allows for the fabrication of ferrites with customizable properties. Metal conjugate ferrites such as zinc, manganese, magnesium, cobalt, copper, nickel, and magnetite are synthesised using these green routes, highlighting the versatility and efficacy of green synthesis techniques in materials fabrication. Furthermore, the biomedical applications of cubic spinel ferrites are elucidated, illustrating their utility in cancer therapy, antibacterial properties, biosensing and drug delivery systems. This review emphasizes the importance of using green chemistry principles and natural resources to advance sustainable material development methods, as well as fully utilising cubic spinel ferrites in various medicinal domains to enhance innovation and tackle global challenges in a sustainable way. [Display omitted] [ABSTRACT FROM AUTHOR]

Photocatalysts play an important role in the effective removal of organic effluents and are considered the best material for this purpose. In the current study, zinc ferrite (ZF), strontium, and holmium co-doped zinc ferrite (SHZF) and composite with the CNTs (SHZF@CNTs) were prepared. Various characterization techniques were used to check their successful synthesis, catalytic activity, and electrochemical properties. The Debye Scherrer formula was used to calculate the crystallite size of the synthesized samples. Electrochemical impedance spectroscopic analysis was performed, and it showed that the prepared CNTs-based composite showed less resistance than bare and co-doped samples. Crystal violet (CV) and phenol were employed as model organic effluents. SHZF@CNTs showed 93.26 % and 57.64 % degradation of CV and phenol, respectively. SHZF@CNTs showed higher degradation efficiency than other as-fabricated samples due to the presence of carbon nanotubes. A radical trapping experiment was also performed to investigate which species are more active during the redox reaction for the photodegradation of organic compounds. [ABSTRACT FROM AUTHOR]

Zinc-incorporated manganese ferrite in polyvinylpyrrolidone matrices was successfully synthesized via a co-precipitation method at 1000 °C. Zn2+ doping was found to have a notable effect on the structural properties of the sample, as evidenced by XRD results indicating a cubic FCC structure with a ferrite spinel structure. The average crystallite size was 20.61 nm, and the lattice parameters of the samples varied slightly depending on the amount of Zn2+ doping. It was observed that Zn2+ doping increases both the magnetic moment and temperature of the sample. Zn2+ ions possess a large magnetic moment, which interacts with the other ions in the sample, resulting in an increased overall magnetic moment and coercivity. FE-SEM microstructure revealed cauliflower morphology, multiple pores, and rough aggregates. This increased magnetic moment was reflected in a specific capacitance value of 53.518Fg−1 at a scanning rate of 30mVs−1. Impedance analysis reveals that the relaxation phenomenon is highly dependent on concentration and frequency. PVP-coated Zinc-incorporated manganese ferrites are of great importance in technology and science due to their high saturation magnetization and low core losses. These ferrites have been widely utilized in electronic applications, such as magnetic storage devices, sensors, and microwave devices. [ABSTRACT FROM AUTHOR]

This work presents the optical properties of nickel zinc ferrite, nickel copper zinc ferrite, and nickel cobalt zinc ferrite films prepared on Si/SiO2 substrates using the sol-gel and spin-coating technique. A J.A. Woollam Company RC2 model D variable angle spectroscopic ellipsometer was used to measure the amplitude ratio (Ψ) and phase difference (Δ) of the films annealed at two distinct temperatures (500 and 800 °C). Measurements were taken at three incident angles (55°, 65°, and 75°) across the spectral range of 190–1000 nm, with a step size of 1 nm. The acquired data were subjected to modeling using a summation of Kramers–Kronig consistent oscillators to determine the film thickness and complex optical functions (refractive index and extinction coefficient) with a minimized mean-squared error. Additionally, incorporating a surface roughness layer notably enhanced the accuracy, with the roughness described using the Bruggeman effective medium approximation reflecting a 50%–50% mixture between the film's optical constants and those of air (void). The experimental and simulated (Ψ, Δ) spectra as a function of wavelength at angles 55°, 65°, and 75° for the NZF, NCuZF, and NCoZF films annealed at 500 and 800 °C are provided. The refractive index and extinction coefficient values as a function of wavelength for NZF, NCuZF, and NCoZF films annealed at 500 and 800 °C are also included. The elucidated optical properties of these films hold potential for application in various optoelectronic devices, including solar cells. [ABSTRACT FROM AUTHOR]

This work describes the synthesis, characterization, and photocatalytic evaluation of a polypyrrole-reinforced zinc-nickel mixed metal ferrite (PPy@ Zn 0.5 Ni 0.5 Fe 2 O 4) nanohybrid. A facile hydrothermal process is employed to synthesize the nanostructured zinc-nickel mixed metal ferrite (ZNF), and in situ oxidative polymerization is utilized to create the PPy nanohybrid. In this nanohybrid, PPy plays multiple roles: preventing charge recombination, reducing photocorrosion, mitigating particle aggregation in ZNF, and enhancing charge transfer and visible light absorption. The combined electron-capturing ability, intrinsic conductivity, and extensive π-conjugation of PPy, along with the magnetic nature of ZNF, render the PPy@ZNF catalyst highly efficient. The results of photoluminescence, impedance, and UV/Vis analysis confirm that PPy plays a critical role in enhancing photocatalytic performance by facilitating charge transfer and extending visible-light absorption. In practical environmental applications, the PPy@ZNF nanohybrid demonstrated superior photocatalytic activity compared to ZNF alone, degrading 98.5 % of malachite green dye under W-lamp light within 80 min, with a rate constant of 0.031 min−1. Scavenger and cyclic experiments identified the active species involved in dye degradation and assessed the reusability of the nanohybrid. Extensive testing revealed the optimal conditions for photocatalytic efficiency; the considered variables included light intensity, catalyst dose, dye concentration, temperature, irradiation time, and pH. These findings suggest that the PPy-reinforced ZNF nanohybrid offers cost-effectiveness, magnetic recoverability, structural stability, and high efficacy as a visible light-driven catalyst, making it a promising candidate for diverse environmental remediation applications. [Display omitted] [ABSTRACT FROM AUTHOR]

The primary goal of our research is to develop a photocatalyst capable of degrading organic molecules in water, achieved through the rare earth Yb3+ doping of Zn-Mg spinel ferrites. A key element of our approach is the use of the conventional sol-gel auto-combustion process, which has proven to be an effective method for synthesizing a high-performing, visible light-driven Zn 0.9 Mg 0.1 Fe 2- x Yb x O 4 (x = 0.000, 0.015, 0.030, 0.045, 0.060 and 0.075) nano-ferrites. Many analytical techniques were employed to evaluate the material's physicochemical characteristics, including P-XRD, EDX, FE-SEM, HR-TEM, FTIR, UV–vis, BET, VSM, EIS, and photocatalysis was carried out against the RhB. The impact of Yb3+ ion doping on the material's crystallite size and lattice parameter has been evaluated. It was found that all the samples' crystallite sizes increased between 33 and 41 nm. These magnetite nanoparticles have spherical forms and nanometric particle sizes, as revealed through field scanning electron microscopy (FE-SEM). The FTIR spectra bands at ʋ 1 (518–535) and (401–411) ʋ 2 subsequently revealed the spinel structure of the synthesized nano-ferrites. The band gap in zinc manganese ferrite increases from 2.51 eV to 2.92 eV after adding ytterbium. The surface area of the Yb3+-doped Zn-Mg ferries ranges from 23.6 m2/g to 27.8 m2/g, making them an excellent choice for data storage. The investigation of magnetic behavior shows the superparamagnetic behavior of all the samples. The produced sample's determined squareness value indicates the magnetostatic interaction between the particles. Because of the low produced coercive field value, these materials can be used in ferrofluids and hyperthermia therapy applications. Furthermore, with a higher RhB removal of 93.80 %, the Yb3+-doped sample photocatalyst successfully separated carriers generated by sunlight. The Yb3+-doped sample (ZMY-5) photocatalyst showed outstanding stability after one cycle of the stability test, obtaining an outstanding RhB elimination of 93.80 %. Zn 0.9 Mg 0.1 Yb 0.075 Fe 1.925 O 4 photocatalyst has substantial promise for large-scale pollutant treatment due to its simple synthesis method, superior magnetic characteristics, exceptional photocatalytic activity for RhB, and excellent stability. [ABSTRACT FROM AUTHOR]

The prime goal of this novel work is to investigate the efficacy of spinel zinc ferrite as a thermoelectric material and its performance enhancement for high temperature applications. Zn 1-x Ni x Fe 2 O 4 (0 ≤ x ≤ 0.2) were prepared by sol-gel method and their structural, morphological, and thermoelectric behaviours were examined as functions of composition and temperature. Among the studied compositions, Zn 0.8 Ni 0.2 Fe 2 O 4 exhibits the highest electrical conductivity (σ) of 49.83 S/m, the largest power factor of 6.66 μW/mK2, and the lowest thermal conductivity (κ) of 0.36 W/mK at 947 K, thus extending to an overall enhancement in the thermoelectric figure of merit (zT). Conduction through electron hopping is proven to be the main driving force for the enhancement in electrical and thus thermoelectric properties. Results reveal that thermoelectric properties of ZnFe 2 O 4 can potentially be enhanced by the doping Ni at Zn site and opens up an exciting opportunity for the utilization of this spinel ferrite as a novel thermoelectric material for applications involving elevated temperatures. [Display omitted] • Thermoelectric figure of merit of ZnFe 2 O 4 was considerably enhanced by doping Ni. • Electron hopping is found to be one of the major contributors for the enhancement of electrical conductivity. • The dopant is also effective in reducing the thermal conductivity of ZnFe 2 O 4 at higher temperatures. • The results indicate that the studied material is suitable for high temperature (>700K) thermoelectric applications. [ABSTRACT FROM AUTHOR]

The present work reports photocatalytic degradation of cetirizine hydrochloride (CTZ-HCl) utilizing polypyrrole (PPy) nanohybrids with ZnFe2O4 (ZnFe) nanoparticles. The synthesized materials were characterized using UV–visible spectroscopy, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), photoluminescence (PL) spectroscopy, BET, and scanning electron microscopy (SEM) techniques. UV diffuse reflectance studies (UV-DRS) revealed that the band gap was found to decrease with increase in the loading of PPy and Kubelka–Munk plots confirmed the bandgap values to be 2.14 eV for ZnFe, 1.94 eV for 1% PPy/ZnFe, 1.66 eV for 3% PPy/ZnFe, and 1.38 eV for 5% PPy/ZnFe. The photocatalytic performance against CTZ-HCl degradation was performed under visible light irradiation for 60 min. The effect of catalyst dosage and the effect of drug concentration were investigated to confirm degradation behavior of the PPy/ZnFe photocatalysts. The degradation followed the pseudo-first-order kinetics model. Maximum photocatalytic degradation was observed to be 98% within 60 min using 5% PPy/ZnFe as the photocatalyst. The recyclability tests revealed that the 5% PPy/ZnFe photocatalyst was reusable up to 4 cycles. Radical scavenging studies confirmed the generation of ●OH radicals that were responsible for the drug degradation. The degraded fragments were analyzed using LCMS technique and the tentative mechanism of degradation was proposed. [ABSTRACT FROM AUTHOR]

The current study investigating the preparation and application of a Multiferroic nano-scale silver zinc ferrite substance (Ag0.5Zn0.5Fe2O4 nanocatalyst) has been established. Multiferroic silver zinc ferrite substance is prepared by co-precipitation technique as hybridized composite. This synethsized nanoparticles was characterized via X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM) as well as Scanning Electron Miscospopy (SEM). Such nanoparticles are used as a sustainable recyclable photo-Fenton's reagent precursor for treating insecticide in wastewater. The results revealed a high Acinate oxidation rate reached to 97% removal within 40 min of irradiance time. To increase the performance, the operating variables are optimized. pH 3.0 and 40 and 400 mg/L for Ag0.5Zn0.5Fe2O4 and hydrogen peroxide, respectively are identified as the optimum values. Also, kinetics and thermodynamic are evaluated and the reaction is subsequent the first-order kinetics model and exothermic and non-spontaneous in nature with a low energy barrier of 35.02 kJ/mol. The advantage of Ag0.5Zn0.5Fe2O4 catalyst is its sustainability since it recovered for multiple reuse with a high activity reached to 80% removal rate after six cyclic use compared to 97% of fresh catalyst use. [ABSTRACT FROM AUTHOR]

The development of a pH‐responsive, biocompatible polymeric carrier for controlled delivery of bioactive agents holds significant practical value for pharmaceutical applications. In this study, we used the gelation method to make pH‐responsive polymeric microbeads using sodium alginate (SA), poly(vinylpyrrolidone‐co‐vinyl acetate) (PVPVA), and nickel zinc ferrite (NZF) nanoparticles for controlled release of doxorubicin (DOX). The generated microbeads are characterized using various techniques, including Fourier‐transform infrared spectroscopy, X‐ray diffraction, scanning electron microscopy, and transmission electron microscopy. Swelling studies reveal enhanced permeability at pH 6.4, and in vitro release studies demonstrate a higher release rate at pH 6.4 compared to pH 2.0. Cytotoxicity tests on MCF‐7 cells (a type of breast cancer cell line) showed that NZF‐loaded microbeads, especially SP‐NZFNPs‐DOX, were more effective than other carriers, indicating their potential usefulness in cancer treatment. Furthermore, biocompatibility tests demonstrate that the SA/PVPVA microbeads and nanoparticles are biocompatible with 3T3 fibroblasts. This study contributes valuable insights to the evolving landscape of nanotechnology in cancer treatment, emphasizing the synergistic role of NZF nanoparticles, SA, and PVPVA in optimizing drug delivery systems. [ABSTRACT FROM AUTHOR]

In order to solve problems of high energy consumption and high carbon emissions in the process of separation zinc and iron from the neutral leaching residue using the fire methods, as well as poor leaching selectivity in the process of separation zinc and iron using the wet methods, and potassium iron vanadium slag and needle ore produced by the process of iron removal from the leachate need to be treated, the technique of separation iron and zinc by oxalic acid was proposed, and the response surface method was used to optimize the conditions for iron-zinc separation, and regression models for predicting iron and zinc leaching rates were established. Meanwhile, the mechanisms of iron-zinc separation and the behavior of the associated metals were discussed in the process of separation. The results show that it is necessary to make full use of the acidity of oxalic acid, the complexation of C2O42- with Fe3+, the property of C2O42- and Zn2+ to form insoluble ZnC2O4 to decompose ZnFe2O4 for achieving the separation of iron and zinc in the neutral leaching residue. The optimization process conditions for iron-zinc separation predicted by the response surface method are as follows: (C2O42-)TOT excess 1. 75 times of the theoretical quantity, leaching time of 170 minutes, temperature of 95 °C and liquid-solid ratio of 8 mL/g, the predicted and the actual values of iron and zinc leaching rates are 91. 48%,0. 63% and 91. 35% and 0. 64% respectively. In the process of iron-zinc separation, 91. 35%Fe is leached into the leachate as Fe(C2O4)33- and Fe(C2O4)22-, 99. 36%Zn,94. 24%Cu and 94. 42%Pb are enriched into the leaching residue as ZnC2O4, CuC2O4 and PbC2O4. It is proved that oxalic acid can decompose ZnFe2O4 at low temperature and separate iron and zinc in the neutral leaching residue, and the separation process does not discharge CO2, the technical defects of the existing iron and zinc separation process by fire methods and wet methods are solved. [ABSTRACT FROM AUTHOR]

The paper focuses on the potential of magneto-fluorescent nanostructures intended to join simultaneously several functions of dissimilar core and shell material into a single entity. Two different types of magneto-fluorescent nanostructures with a broad array of physicochemical properties are premeditated and collated here. Strontium hexaferrite (Hard ferrite) core with CdS shell and Nickel Zinc ferrite (Soft ferrite) core with CdS shell are the two sets of magneto fluorescent nanostructures that were designed. Magnetic and optical analysis of both sets provides divergent outcomes. The shape of the derivative hysteresis curve gives a direct indication of the dissimilar nature (superparamagnetic & Permanent magnetic) of magnetic cores respectively. Optical results depict that both sets of magneto-fluorescent nanostructures are highly stable showing emission only in the position of the CdS shell only. [ABSTRACT FROM AUTHOR]

MnZn ferrite powders were prepared, based on the novel nano-in-situ composite method and through chemical sol–spray–calcination technology. Different dosage of CTAB were used, and the influences on the precursor sol solutions and precursor powders were studied. Also, the selected precursor powders (P-0.1CTAB) were calcined at 1060 °C in air for 3 h, and the sample (S-0.1CTAB) was considered to further exploration. The results indicated that the precursor sol and precursor powders were in their optimal state when adding 0.1 wt.% CTAB. Under this condition, the Zeta potential of the sol was 10.7 mV, and the colloidal particle size was 91.63 nm. The corresponding precursor powders can still maintain a nanoscale fine particle composition and be well dispersed. The S-0.1CTAB sample with hollow spherical shell composed of small particles of several hundred nanometers had pure MnZn ferrite phase, and the maximum value of saturation magnetization (Ms) was 53.46 emu/g. Moreover, there are three stages of the formation of MnZn ferrite during the CTAB-assisted synthesis process which are CTAB ionization and (Mn, Zn, Fe)(OH)(NO3)(H2O) formation stage, CTA + adsorption and colloidal particle formation stage, and (Mn, Zn, Fe)(OH)(NO3)(H2O) decomposition stage. [ABSTRACT FROM AUTHOR]

A new series of 6‐methoxy‐2‐naphthalene based pyrimidinones were synthesized via one pot‐three component synthetic reaction of aryl aldehydes, 6‐methoxy‐2‐acetonapthone and urea in the presence of nano zinc ferrite catalyst under conventional method. The synthesized compounds were characterized by their spectral techniques including FT‐IR, H1, C13 NMR, LCMS, and analysis of elements. Molecular docking analysis was also performed to identify the protein‐ligand interactions and binding energy of synthesized compounds. Biological studies of all synthesized pyrimidinone compounds have been measured against bacterial and fungal strains by calculating the zone of inhibition. [ABSTRACT FROM AUTHOR]

In this project, five different nanoparticles based on different ratios of iron, zinc, and manganese were synthesized to form Znx Mn1-X Fe2O4. Then, one of them was selected and polyethylene glycol was conjugated to its surface using tartaric acid to improve its biocompatibility. Also, to improve the target ability of the prepared polyethylene glycol conjugated Znx Mn1-X Fe2O4 as a nano-platform, folic acid was used as a targeting agent. The nano-platform was characterized using different techniques such as X-ray diffractometey, vibrating-sample magnetometer, ultraviolet–visible spectroscopy, field emission-scanning electron microscopy, Fourier-transform infrared spectroscopy and thermogravimetric analysis. In vivo and in vitro tests including hemolysis, blood aggregation and lethal dose showed that Zn0.5Mn0.5 Fe2O4 were the most suitable photosensitizers among all. Also, in vivo and in vitro biocompatibility analysis revealed that incorporation of polyethylene glycol can significantly improve the biocompatibility of the nano-platforms. The cytotoxicity results revealed that cell viability of cancerous cells was lower when the nano-platform was coated with folic acid and poly ethylene glycol under irradiation of visible light while whiteout shining the light, the cell viability was almost 100% for polyethylene coated nano-platform. These results can prove the great potential of folic acid to improve the photodynamic therapy performance of Zn0.5Mn0.5 Fe2O4. [ABSTRACT FROM AUTHOR]

A humidity sensor array can be used in applications requiring non-contact sensing and contactless interface localization, which became a significant area of research after COVID-19 and reduced the risk of bacterial transmission associated with conventional touch displays. In this study, a thin film humidity sensor has been designed using calcium (Ca) doped zinc ferrite (ZnFe2O4) nanomaterial, which has been prepared by the sol-gel auto-ignition process. The synthesized nanomaterial was characterized using Powder X-Ray Diffraction (PXRD), Fourier Transform Infrared (FTIR) spectroscopy, Field Emission Scanning Electron Microscopy (FESEM), and Energy Dispersive X-Ray (EDX) techniques. The doping of Ca reduces the crystallite size and increases the lattice constant. Attempts have been made to determine the different humidity sensing parameters. The developed humidity sensor has a response time of 12 seconds and a recovery time of 66 seconds. The developed humidity sensor has good repeatability and a negligible aging effect. [ABSTRACT FROM AUTHOR]

Methylene blue is widely used in various industries, such as textile. Notably, wastewater generated from these industries represents a significant source of water pollution. To solve this problem, the use of photocatalysts for the degradation of methylene blue in wastewater has attracted the attention of many researchers. In this study, manganesezinc ferrite nanoparticles doped with dysprosium with the chemical composition of Mn0.8Zn0.2Fe1.95Dy0.05O4 were utilized as photocatalyst for the degradation of methylene blue dye. Initially, the nanoparticles were synthesized using a self-combustion sol-gel method, and their phase composition and microstructural characteristics were evaluated through X-ray diffraction and field emission scanning electron microscopy, respectively. The XRD patterns confirmed the formation of manganese-zinc ferrite nanoparticles with an average crystallite size of 28.38 nm within a spinel structure. Additionally, FE-SEM micrographs indicated an average particle size of approximately 99.28 nm for the nanoparticles. Subsequently, the influence of different values of the synthesized manganese-zinc ferrite nanoparticles (0.0, 0.1, 0.2, and 0.3 g/lit) on the degradation of methylene blue dye was investigated. The results demonstrated that the presence of these nanoparticles significantly affected the degradation rate of methylene blue. Ultimately, the findings indicated that the addition of 0.1 g/lit of these nanoparticles yielded the most effective results, achieving approximately 87.25% degradation in 12 h. [ABSTRACT FROM AUTHOR]

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Double ferrite nanocomposites with NiF 2 O 4 as the core and ZnFe 2 O 4 as the shell, were synthesised through combination of co-precipitation and hydrothermal methods. This two-step process resulted in formation of a cubic structured core of around 100 nm and a shell of zinc ferrite nanoparticles which are below 10 nm in size. The core/shell structures were characterised using various techniques such as XRD, Raman, TEM/EDS and VSM. In addition, Ni leaching out of these structures was tested in the ultra-pure water and saline solution. These analyses demonstrated that the shell of zinc ferrites effectively prevents Ni leaching from the core keeping the concentration of nickel well below the level usually found in drinking water. These core/shell nanocomposites exhibit a ferrimagnetic behaviour. [ABSTRACT FROM AUTHOR]

The permeability of the Fe Soft Magnetic Composite (SMC) materials need further improve to broaden their application prospect. This research work presents a novel high permeability SMC material which has a low core loss (P cv). The Fe particles formed an elongated strip shape structure through the ball milling process, and the high permeability Mn 0.5 Zn 0.5 Fe 2 O 4 ferrite phase was formed around the elongated strip shape Fe particles via a high temperature in-situ reaction process (ZnO + MnO + Fe 2 O 3 –Mn 0.5 Zn 0.5 Fe 2 O 4). While the added high resistive SiO 2 phase aggregated at the long strip shape Fe particle outer surface and effectively increased the resistivity of the SMCs. As the percentage of the Mn 0.5 Zn 0.5 Fe 2 O 4 ferrite coating increase, the permeability of the double layer coated SMCs gradually increased from 38 for the 1 wt% Mn 0.5 Zn 0.5 Fe 2 O 4 coated SMCs to 170 for the 18 wt% Mn 0.5 Zn 0.5 Fe 2 O 4 coated SMCs. The 3 wt% Mn 0.5 Zn 0.5 Fe 2 O 4 coated SMCs has the lowest core loss (P cv) of 86.9 W/kg at 10 mT, 500 kHz. [ABSTRACT FROM AUTHOR]

Environmental pollution, being a major concern worldwide, needs a unique and ecofriendly solution. To answer this, researchers are aiming in utilizing plant extracts for the synthesis of nanoparticles. These NPs synthesized using plant extracts provide a potential, environmentally benign technique for biological and photocatalytic applications. Especially, plant leaf extracts have been safe, inexpensive, and eco-friendly materials for the production of nanoparticles in a greener way. In this work, zinc ferrite nanoparticles (ZnFe2O4 NPs) were prepared using Nyctanthes arbor-tristis leaf extract by hydrothermal method, and its biological and photocatalytic properties were assessed. The synthesized ZnFe2O4 NPs were characterized using powder X-ray diffraction (XRD), scanning electron microscopy (SEM), and Fourier-transform infrared spectroscopy (FT-IR). X-ray diffraction confirmed the arrangement of the fcc crystal structure of the nanoparticles and that some organic substances were encapsulated within the zinc ferrite. According to the SEM analysis, the resulting nanoparticles got agglomerated and spherical in shape. The ZnFe2O4 nanoparticles are in their pure form, and all of their elemental compositions were shown by the energy-dispersive X-ray analysis (EDAX) spectrum. The FTIR results revealed that the produced nanoparticles contained distinctive functional groups. Fluorescence spectroscopy was used to examine the binding affinities between bovine serum albumin (BSA) and ZnFe2O4 nanoparticles in terms of protein binding, stability, and conformation. The interaction between BSA and ZnFe2O4 NPs was examined using steady-state and time-resolved fluorescence measurements, and it was evident that static quenching occurred. The ability of ZnFe2O4 nanoparticles to kill Culex quinquefasciatus (C. quinquefasciatus) larvae was evaluated. The synthesized NPs demonstrated a noteworthy toxic effect against the fourth instar larvae of C. quinquefasciatus with LC50 values of 43.529 µg/mL and LC90 values of 276.867 µg/mL. This study revealed the toxicity of green synthesized ZnFe2O4 NPs on mosquito larvae, proving that these NPs are good and effective larvicides. Furthermore, the ZnFe2O4 NPs were utilized for dye degradation of methylene blue under visible light treatment and achieved 99.5% degradation. [ABSTRACT FROM AUTHOR]

The principal intention of the currently analysis is to investigate the impacts of the naturally convective nanofluid using a model of Carreau fluid with engine oil (C n H 2 n + 2) as the base fluid and Manganese Zinc Ferrite (M n Z n Fe 2 O 4) as the nanoparticle, the fluid flowing through a stretched cylinder in a fuzzy ambient. It examines the impact of assorted parameters, Weissenberg number (We) , Prandtl numeral (Pr) , Schmidt numeral (Sc) , and curvature (k) with magnetic field (B) and nanoparticle parameter, in order to manipulate an analogous conversion, the regulating equations of velocity, energy, and concentration profiles permute from a set of partial differential equations stand to ordinary differential equations. The present analysis focuses on the no slip assumption, which gives rise to a nonlinear Dirichlet boundary condition in axial velocity. The bvp5c approach was utilized to solve the resulting series of equations by the MATLAB. This is a highly effective approach with minimal computing expenditure. The volume quantity of nanoparticles in M n Z n Fe 2 O 4 is considered an uncertain parameter respect to TFNs (triangular fuzzy numbers) ranging [0, 0.5, 0.1]. Triangular membership function (TMF) is used to study the uncertainty variability while α − cut controls the TFNs. Fuzzy linear regression analysis makes use of TFNs to determine the middle (crisp), left, and right values of the fuzzy velocity profile. In comparison to the crisp velocity profile (mid value), the study's result and the fuzzy velocity profile have the maximum rate of flow. Tables and graphs are used to illustrate the outputs. [ABSTRACT FROM AUTHOR]

Arsenic, cadmium, chromium and nickel are categorized as carcinogen 1. Among these, arsenic is most toxic, which accumulates in the body cells and cause serious diseases like cancer, kidney failure, lungs and chest problems. In this project, In-Situ Graphene oxide/Zinc Ferrite (GO/ZnFe2O4) nanocomposites (NCs) were synthesized using modified Hummer's assisted with precipitation method. The NCs were characterized by UV/Visible spectroscopy, X-ray diffraction (XRD) analysis, Field emission scanning electron microscopy (FESEM), Energy dispersive X-ray (EDX) and Fourier transformed infrared (FTIR) spectroscopy. XRD confirms the formation of NCs with average crystallite size 47 nm, 34 nm and 28 nm for GO/ZnFO(10:5), GO/ZnFO(5:2.5) and GO/ZnFO(1:0.5) respectively. The GO/ZnFe2O4 NCs were used for adsorption of As(III) from aqueous solution under the influence of time, concentration and temperature. Batch adsorption experiments were conducted to evaluate the adsorption capacity which was found in the range 80 to 98% at lower concentrations. The kinetic data followed pseudo second order. The As(III) removal data was tested for Langmuir and Freundlich adsorption models. However, Langmuir model was found better fitted. The results obtained show that GO/ZnFe2O4 NCs are effective and economically valuable adsorbents for removing As(III) ions. [ABSTRACT FROM AUTHOR]

The processing of fine dust from copper smelters in Kazakhstan is an urgent task. The currently used technology of hydrometallurgical dust processing, which involves leaching with sulfuric acid to produce lead cake and a solution containing copper and zinc, fails meet modern requirements. The significant content of arsenic in the dust (up to 15%) hinders the production of high-quality products. In this study, fine dust from a copper smelter in Kazakhstan, obtained following conversion of copper mattes from autogenous smelting in Vanyukov furnaces, was used. Comprehensive analytical studies of the elemental and phase composition of dust were carried out using a Bruker D 8 ADVANCE X‑ray diffractometer and a scanning electron microscope with a JED-2300 energy dispersive X‑ray spectrometer (JEOL). This ensured the reliability of the data on the elemental composition of the initial dust, which were subsequently used to examine the behavior of arsenic and other non-ferrous metals under conditions of reduction roasting with natural gas. In order to gain a deeper understanding of the mechanism of the reduction roasting, a detailed thermodynamic analysis was carried out to examine the interactions between dust components and natural gas within the temperature range of 500–1000 K. Thermodynamic calculations were carried out using Outotec HSC Chemistry 8.1.5 software. It was established that favorable conditions are created for the reduction of zinc and copper ferrites, as well as arsenic oxide (As5+) when roasting dust with natural gas. It was demonstrated that the preliminary roasting of dust with natural gas ensures the most effective reduction of arsenic oxide (As5+) and the production of arsenic-free calcine with the subsequent high selective separation of Pb, Cu, and Zn from it into commercial products. The use of this method will significantly improve the technological performance of leaching fine dust with sulfuric acid due to the preliminary maximum removal of arsenic from the general technological scheme and the destruction of copper and zinc ferrites, which are relatively insoluble in acid, to their readily soluble oxides, with their subsequent dissolution. [ABSTRACT FROM AUTHOR]

In awareness of industrial dye wastewater, carbon quantum dots (CQDs) and cobalt zinc ferrite (CZF) nanocomposites were synthesised for the making of carbon quantum dots coated cobalt zinc ferrite (CZF@CQDs) nanophotocatalyst using oxidative polymerization reaction. The results of TEM, zeta potential value, and FTIR confirm highly dispersed 1–4 nm particles with the − 45.7 mV carboxylic functionalized surface of CQDs. The results of the synthesised CZF@CQDs photocatalyst showed an average particle size of ~ 15 nm according to TEM, SEM, and XRD. The photocatalyst showed a 1.20 eV band gap, which followed the perfect visible light irradiation. TGA and DTA revealed the good thermal stability of the nanophotocatalyst. VSM was carried out, and the saturation magnetisations for CZF and CZF@CQDs were 42.44 and 36.14 emu/g, respectively. A multipoint study determined the BET-specific surface area of the CZF@CQDs photocatalyst to be 149.87 m2/g. Under visible light irradiation, the final CZF@CQDs nanophotocatalyst demonstrated remarkable efficiency (~ 95% within 25 min) in the photocatalytic destruction of Reactive Blue 222 (RB 222) and Reactive Yellow 145 (RY 145) dyes, as well as mechanical stability and recyclability. Even after the recycling of the degradation study, the nanophotocatalyst efficiency (~ 82%, 7th cycles) was predominantly maintained. The effects of several parameters were also investigated, including initial dye concentration, nanophotocatalyst concentration, CQD content, initial pH of the dye solution, and reaction kinetics. Degradation study data follow the first-order reaction rate (R2 > 0.93). Finally, a simple and low-cost synthesis approach, rapid degradation, and outstanding stability of the CQD-coated CZF nanophotocatalyst should make it a potential photocatalyst for dye wastewater treatment. [ABSTRACT FROM AUTHOR]

In the present work, raw materials, namely zinc acetate dihydrate, iron nitrate nonahydrate, and solvent 2-methoxyethanol, were utilized to synthesize zinc ferrite nanoparticles by sol–gel method. The synthesized material was annealed at different temperatures of 500 °C, 600 °C, and 700 °C to study its effect on morphological, optical, and magnetic properties. Formation of single phase spinel cubic structure with intense peak orientation along (311) direction was confirmed by powder X-ray diffraction pattern. FESEM and EDX spectra of the annealed samples confirmed the surface morphology and elemental composition. UV–visible spectral analysis was used to examine the optical properties of the samples. VSM at room temperature revealed the ferromagnetic behavior of zinc ferrite nanoparticles. All the prepared samples at different annealing temperatures showed good antibacterial properties against different bacterial strains. [ABSTRACT FROM AUTHOR]

The main finding of this work focuses on the numerical analysis of magnetized Casson hybrid nanofluid flow via porous moving wedge with surface-catalyzed reactions. Thermal radiation and chemical reactions are also investigated as heat and mass transport mechanisms. Feature of hybrid nanofluid, which contains nanoparticles, such as nickel zinc ferrite (NiZnFe2O4) and manganese zinc ferrite (MnZnFe2O4) nanoparticles with engine oil as a working fluid, is discussed. These hybrid nanofluids (NiZnFe2O4 + MnZnFe2O4/C2H18) offer significant improvements in thermal conductivity, heat transfer efficiency, and magnetic control, making them ideal for automotive, industrial, and magnetic fluid applications. The flow dynamics of the system have been modeled using a system of non-linear PDEs, which are transformed into dimensionless ODEs using appropriate similarity conversions. The transformed ODEs are solved using the fourth- and fifth-order Runge–Kutta–Fehlberg method along with the shooting technique. Results indicate that increased surface-catalyzed parameters in porous media accelerate heterogeneous catalysis, leading to more vigorous reactions and shorter reaction times. Furthermore, the incorporation of NiZnFe2O4 and MnZnFe2O4 nps in the base fluid substantially improves both the velocity and energy transmission rate. Engine oil containing ferrite nanoparticles on porous moving wedge could improve engine performance and efficiency in automotive cooling systems and lubrication effectiveness. [ABSTRACT FROM AUTHOR]

This manuscript presents a comprehensive study on the optical, dielectric, and electrical properties of Al- and Cu-doped barium hexaferrite/cobalt–zinc-ferrite hybrid nanocomposites. The main objective of the study is to investigate how the concentration of two different materials, namely BaFe12−0.5Al0.5O19 and BaFe12−0.5Cu0.5O19, affects the optical, dielectric, and electrical properties in the production of a composite material or the influence of Co0.6Zn0.4Fe2O4. The optical behaviour of the nanocomposite was investigated using UV–visible spectroscopy to obtain the absorption spectra. The dielectric and electrical behaviour was extracted from the absorption spectra, and the electrical properties of the nanocomposites were calculated using a simple theoretical model that requires only two parameters: the effective mass of the charge carriers and the activation energy determined from the Urbach and dielectric constants. The results show that the concentration of the hard-phase BaFe12−xMxO19 (M = Al, Cu) significantly influences the physical properties. The optical density showed peaks at 450 nm and 550 nm for the Al- and Cu-doped nanocomposites, indicating differences in their electronic structure. The skin depth showed an initial decrease followed by an increase, with minimum values of 400–500 nm and 500–600 nm for the two composites, respectively. The refractive index of 3.0–3.4 corresponds to semiconductors such as mercury sulphide and silicon and enables optoelectronic applications. The high transmittance of 400–800 nm is also suitable for temperature control and radiation shielding of spacecraft. By adjusting the BaFe12−xMxO19 concentration, the refractive index and reflectivity can be adjusted. Increased optical conductivity in the visible range reveals potential as an optical conductor. The dielectric constant and the loss factor also change with the composition, which enables the dielectric behaviour to be tuned. The real part of the dielectric constant increased exponentially while the imaginary part peaked around 2.2–2.8 eV, related to inter-band transitions. Both composites showed positive dielectric loss at higher energies, suggesting relaxation phenomena. Overall, the multifunctional nanocomposite holds promise for various applications including optoelectronics, photocatalysis, sensing, and rewritable memory that require low saturation magnetization and coercivity. The findings contribute to the development of advanced materials with desirable properties for modern technological applications. [ABSTRACT FROM AUTHOR]

This report is on magneto-electric (ME) interactions in bulk composites with coaxial fibers of nickel–zinc ferrite and PZT. The core–shell fibers of PZT and Ni1−xZnxFe2O4 (NZFO) with x = 0–0.5 were made by electrospinning. Both kinds of fibers, either with ferrite or PZT core and with diameters in the range of 1–3 μm were made. Electron and scanning probe microscopy images indicated well-formed fibers with uniform core and shell structures and defect-free interface. X-ray diffraction data for the fibers annealed at 700–900 °C did not show any impurity phases. Magnetization, magnetostriction, ferromagnetic resonance, and polarization P versus electric field E measurements confirmed the ferroic nature of the fibers. For ME measurements, the fibers were pressed into disks and rectangular platelets and then annealed at 900–1000 °C for densification. The strengths of strain-mediated ME coupling were measured by the H-induced changes in remnant polarization Pr and by low-frequency ME voltage coefficient (MEVC). The fractional change in Pr under H increased in magnitude, from +3% for disks of NFO–PZT to −82% for NZFO (x = 0.3)-PZT, and a further increase in x resulted in a decrease to a value of −3% for x = 0.5. The low-frequency MEVC measured in disks of the core–shell fibers ranged from 6 mV/cm Oe to 37 mV/cm Oe. The fractional changes in Pr and the MEVC values were an order of magnitude higher than for bulk samples containing mixed fibers with a random distribution of NZFO and PZT. The bulk composites with coaxial fibers have the potential for use as magnetic field sensors and in energy-harvesting applications. [ABSTRACT FROM AUTHOR]

We report the measurement of the optical bandgap in ferrite doped Gd2O3. Doping of the nickel zinc ferrite (Ni0.5Zn0.5Fe2O4) nanoparticles to Gd2O3 powder was done through thermal decomposition of the mixture at 1000 °C. The average grain size of the thermally decomposed mixture was determined to be around 95 nm and contained phases of cubic Gd2O3, GdO, and orthorhombic prisms of GdFeO3. The imaginary part of the complex dielectric function was calculated from the absorbance measurements that showed an optical bandgap at 1.8 eV. The observed value of the fundamental energy gap is on average 4.0 eV smaller than suggested by early experiments. A model for the ferrite doped Gd2O3 was constructed to suggest that the Ni, Zn, and Fe atoms occupy Gd sites in the Gd2O3 lattice. A new band at Γ point is formed due to the hybridization of the atomic orbitals of dopant and Gd3+ that shifts the fundamental absorption edge to the red part of the photon energy spectrum. Despite having a high density of negatively charged carriers contributed by the dopant, the onset of the direct interband transitions is clearly resolved. [ABSTRACT FROM AUTHOR]

We report the measurement of the optical bandgap in ferrite doped Gd2O3. Doping of the nickel zinc ferrite (Ni0.5Zn0.5Fe2O4) nanoparticles to Gd2O3 powder was done through thermal decomposition of the mixture at 1000 °C. The average grain size of the thermally decomposed mixture was determined to be around 95 nm and contained phases of cubic Gd2O3, GdO, and orthorhombic prisms of GdFeO3. The imaginary part of the complex dielectric function was calculated from the absorbance measurements that showed an optical bandgap at 1.8 eV. The observed value of the fundamental energy gap is on average 4.0 eV smaller than suggested by early experiments. A model for the ferrite doped Gd2O3 was constructed to suggest that the Ni, Zn, and Fe atoms occupy Gd sites in the Gd2O3 lattice. A new band at Γ point is formed due to the hybridization of the atomic orbitals of dopant and Gd3+ that shifts the fundamental absorption edge to the red part of the photon energy spectrum. Despite having a high density of negatively charged carriers contributed by the dopant, the onset of the direct interband transitions is clearly resolved. [ABSTRACT FROM AUTHOR]

Crystalline ZnFe2O4 (zinc ferrite) material was prepared using the sol–gel technique and converted in the forms of 3 pellets, out of which 2 pellets were irradiated at room temperature by pulsed Nd:YAG laser with 1.5 W, λ = 532 nm named ZF1 and continuous AlGaAs diode laser of 4 W, λ = 808 nm called ZF2, respectively, while the 3rd pellet was kept as control and named ZF. Synchrotron X-ray Diffraction (S-XRD) reveals the marginal variation in the structure having the lattice parameters of 8.4364 Å for ZF, 8.4176 Å for ZF1 and 8.4187 Å for ZF2. The porosity after laser irradiation has been increased to 10.87% for ZF1 and 10.84%, for ZF2 from 10.28% for ZF. The blocking temperature (TB) has been ∼15 K for all samples. There had been a slight variation in the magnetization of irradiated pellets at 5 and 300 K compared to ZF. The separation between ZFC and FC curves, the measure of interaction between Fe ions has increased for irradiated pellets when compared with the separation for ZF. Moreover, magnetization (M) versus applied magnetic field (H) at 5 K in the range of ±1 T shows the ferrimagnetic behaviour and this ordering has been seen up to TB as visible from M-T curves, whereas the material becomes superparamagnetic above TB as observed from M-T & M-H measurements. [ABSTRACT FROM AUTHOR]

In addressing issues related to electromagnetic interference, the demand for ferrite materials with exceptional magnetic and dielectric properties has escalated recently. In this research, sol-gel auto combustion technique prepared Nickel zinc ferrites substituted with cerium, denoted as Ni0.5Zn0.5Ce0.02Fe1.98O4.X-ray diffraction (XRD), Vibrating Sample Magnetometer (VSM), and Field Emissions Scanning Electron Microscope (FESEM) were used to investigate the structure, magnetic properties, and morphology of Cerium doped NiZn Nano ferrites, respectively. The magnetic and dielectric properties of the sample was examined within a frequency range of 2.5–5.5 GHz. Sample exhibits low permittivity (2.2), high permeability (1.4), low dielectric (0.35) and magnetic loss tangent (-0.5) and highest saturation magnetization measuring 30.28 emu/g. A Novel Double-band, 4x4 MIMO window grill-modeled antennas operating on 3.5 GHz and 4.8 GHz frequency bands for 5G smartphones is designed using the CST microwave studio suite. The performance of window grilled 4x4 MIMO antenna model with Cerium doped NiZn nano ferrites as substrate, is investigated and found the return loss of -35 and -32 dB, with the bandwidth of 200MHz, gain (1.89 & 4.38dBi), envelope correlation coefficient (0.00185), channel capacity loss (0.2bps/Hz), and interterminal isolation of (22& 19dB).The results show that the antenna size is reduced with improved bandwidth, higher isolation and better diversity gain performance using Cerium doped NiZn nano ferrite substrate compared to conventional dielectric substrates. [ABSTRACT FROM AUTHOR]

As typical magnetic materials, ferrites and their composites play dominant roles in the design of high-performance electromagnetic wave (EW) absorber. Solvent thermal method is the most popular route for synthesizing ferrites, while systematical comparison research about the influence of reaction solvents of solvent thermal process on ferrite based material's EW absorption performance has rarely been carried out. Thus in this work, we adopted cotton fabric as raw material, and synthesized two kinds of zinc ferrite decorated hollow carbon cloth (CC@ZnFe 2 O 4) composites through solvent thermal reaction where deionized water and ethylene glycol was adopted as reaction solvents, respectively. After comprehensive and detailed comparison of the structures and performances of these two ferrite composites, the CC@ZnFe 2 O 4 synthesized in deionized water phase possesses an ideal optimal absorption efficiency for EW, that is the minimum reflection loss (RL min) of −46 dB, while the effective absorption bandwidth of CC@ZnFe 2 O 4 composites synthesized in ethylene glycol phase is wider (4.9 GHz). The synergistic effect of impedance matching, interface polarization, magnetic resonance, and multiple reflections co-determined the ideal EW absorption performances of these two samples. The research can not only provide new guidance for the secondary utilization of waste textiles, but also become an important reference for the preparation of ferrite based high-performance EW absorbers through solvent thermal method. [Display omitted] [ABSTRACT FROM AUTHOR]

Exploring efficient, abundant, economical and stable materials for sustainable energy applications, such as electrochemical water splitting and supercapacitance, is a challenging task. Mixed transition metal spinel ferrites can rationally be customized to attain these features and deliver enhanced electrochemical activity. The catalytic performance of spinels is remarkably influenced by tuning the cationic occupancy at the tetrahedral or octahedral position. Herein, a set of spinel Ni1‐xZnxFe2O4 (0≤x≤1) nanocomposites were obtained via a scalable solventless thermolysis of metal acetylacetonate precursors at relatively mild temperatures. A suite of techniques such as powder p‐XRD, EDX, SEM, TEM, HRTEM, and SAED were employed to confirm the formation of the Ni−Zn ferrite solid solutions. It was found that small amounts of Ni at tetrahedral sites were beneficial for charge storage and hydrogen evolution. For instance, Ni0.2Zn0.8Fe2O4 nanocomposite demonstrated superior HER activity with a much lower overpotential of 87 mV compared to the pristine NiFe2O4 (213 mV) or ZnFe2O4 (164 mV) catalysts. However, Ni‐occupied tetrahedral sites were not suitable for OER, whereby the pristine ZnFe2O4 displayed high catalytic activity with an overpotential of 330 mV, outperforming other electrode compositions. The study helps to identify suitable compositions and site tuning for HER, OER and supercapacitors. [ABSTRACT FROM AUTHOR]

In this study, zinc ferrite nanoparticles (ZnFe2O4 NPs) were incorporated into a polycarbonate/polyethylene oxide (PC/PEO) blend using the casting method. The resulting blends were subjected to comprehensive analysis using various techniques. X‐ray diffraction (XRD) analysis revealed that the presence of ZnFe2O4 nanoparticles had a significant impact on the crystal structure of the PC/PEO blend, leading to a reduction in crystallinity. Fourier‐transform infrared (FT‐IR) measurements further confirmed the uniform distribution and compatibility of PC and PEO as polymer components, as well as their compatibility with the blend containing ZnFe2O4 NPs. The optical properties of the PC/PEO blend, including band gap and Urbach energy, were quantified using the Kubelka–Munk method. The incorporation of ZnFe2O4 NPs resulted in the formation of sub‐band states between the valence and conduction bands, leading to a decrease in the band gap values. Field emission scanning electron microscopy (FESEM) analysis revealed a noticeable modification in the surface roughness, with the addition of ZnFe2O4 NPs resulting in a smoother surface texture. The electrical properties of the blends, including dielectric constant, dielectric loss, and AC conductivity, were measured. The addition of ZnFe2O4 NPs increased the dielectric constant (ε′) at lower frequencies, while it remained relatively stable at higher frequencies due to the localized charge carriers within the polymer blend. The higher values of ε' observed at lower frequencies can be attributed to the movement of ions, which contributes to enhanced ionic conductivity. The magnetic properties of the blends were evaluated, demonstrating an increase in magnetic saturation upon the addition of ZnFe2O4 NPs. These findings provide valuable insights into the structural, optical, electrical, and magnetic characteristics of PC/PEO blends incorporated with ZnFe2O4 nanoparticles, thereby highlighting their potential for a wide range of technological applications. [ABSTRACT FROM AUTHOR]

In this study, we synthesized a range of spinel ferrite ZnxMg1-xFe2O4 (x = 0, 0.3) forms using the sol-gel method. Additionally, polypyrrole nanosphere supported by magnesium and zinc ferrites (ZnxMg1-xFe2O4@PPy) were synthesized through in-situ polymerisation. The surfaces of ZnxMg1-xFe2O4 (x = 0, 0.3) and ZnxMg1-xFe2O4@PPy were subjected to spectroscopic analysis. The data obtained from X-ray diffraction (XRD) confirmed the formation of Zn-Mg spinel ferrite. The electrochemical analysis results demonstrated that the Zn0.3Mg0.7Fe2O4@PPy nanocomposites exhibited enhanced redox activity and a higher current intensity. This study highlights the development of hybrid Zn0.3Mg0.7Fe2O4@PPy type nanospheres with substantial and effective electrochemical properties, which could be a suitable option for industrial applications. [ABSTRACT FROM AUTHOR]