Ni-Zn Research Articles

An Ultra-Low Self-Discharge Aqueous|Organic Membraneless Battery with Minimized Br2 Cross-Over.

Batteries dissolving active materials in liquids possess safety and size advantages compared to solid-based batteries, yet the intrinsic liquid properties lead to material cross-over induced self-discharge both during cycling and idle when the electrolytes are in contact, thushighly efficient and cost-effective solutions to minimize cross-over are in high demand.An ultra-low self-discharge aqueous|organic membraneless battery using dichloromethane (CH2 Cl2 ) and tetrabutylammonium bromide (TBABr) added to a zinc bromide (ZnBr2 ) solution as the electrolyte is demonstrated. The polybromide is confined in the organic phase, and bromine (Br2 ) diffusion-induced self-discharge is minimized. At 90% state of charge (SOC), the membraneless ZnBr2 |TBABr (Z|T) battery shows an open circuit voltage (OCV) drop of only 42mV after 120 days, 152 times longer than the ZnBr2 battery, and superior to 102 previous reports from all types of liquid active material batteries. The 120-day capacity retention of 95.5%ishigher than commercial zinc-nickel (Zn-Ni) batteries and vanadium redox flow batteries (VRFB, electrolytes stored separately) and close to lithium-ion (Li-ion) batteries. Z|T achieves >500 cycles (2670h, 0.5m electrolyte, 250 folds of membraneless ZnBr2 battery)with ≈100% Coulombic efficiency (CE). The simple and cost-effective design of Z|T provides a conceptual inspiration to regulate material cross-over in liquid-based batteries to realizeextendedoperation.

Single and binary nickel, copper, and zinc-based nanosized oxides as anode materials in lithium-ion batteries

The demand for portable power sources with higher energy density and longer lifespan has prompted researchers to focus on developing better electrode materials for lithium-ion batteries (LIBs). Metal oxide nanoparticles have potential due to their low cost, high surface-area-to-volume ratio, strong reactivity, excellent size distribution, high theoretical capacities, and eco-friendly synthesis methods. However, there is still room for improvement in capacity retention and rate performance. To cope with this entail, the cycle performance of LIBs has been initially investigated utilizing single metal oxide anode materials including NiO, CuO, and ZnO nanostructures. Subsequently, binary oxides of Ni–Cu, Ni–Zn, and Cu–Zn have been synthesized to examine whether the binary structures boost the battery performance. NiCuO is the optimum anode material combining the benefits of NiO with the highest initial discharge capacity of 691 mAh g-1\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$^{-1}$$\\end{document} and the highest retention rate of CuO (49% after 30 cycles).

Health Risk Assessment of Heavy Metals in Lettuce and Spring Onion on Human Health in Kumasi, Ghana.

The demand and consumption of vegetables are significantly increasing worldwide, which has resulted in urban farming on anthropogenic sites. This study assessed the concentrations of some selected heavy metals in lettuce and spring onion in line with the WHO/FAO required standard and its implications on human health. The study was carried out in Kumasi, within moist semi-deciduous forest vegetation, Ghana. The digested samples were analyzed for heavy metals (Cu, Cr, Fe, Mg, Ni, and Zn) using atomic absorption spectrophotometer (AAS Model AA 400p). Analysis of variance was used to test the level of significance at α = .05. The study found mean concentrations of chromium and iron in lettuce and spring onion to be below detection level (BDL) in all study sites based on WHO/FAO permissible level. Also, while copper in lettuce was BDL at all the sites, there were higher mean concentration of copper in spring onion at BSGS (131.5 ± 0.31 mg/kg) and BSG (120.8 ± 0.01 mg/kg). The mean concentration of nickel in lettuce (137.15 ± 0.0231) and spring onion (173.55 ± 0.02 mg/kg) at BSGS were higher than WHO/FAO permissible level. Mean concentration of zinc in both lettuce and spring onion were higher than WHO/FAO permissible level in all the study sites, except zinc in spring onion at KT. The ANOVA test statistics showed no significant difference among the concentrations of heavy metals in all sites, except zinc in lettuce and nickel in spring onion. The study found cancer risk factor for nickel, which exceeded the benchmark of 1 × 10-6 for both lettuce and spring onion, indicating that long-term consumption could increase the risk of cancer in consumers. The study's findings call for strict regulation and regular monitoring of heavy metals in vegetables cultivated at anthropogenic sites in urban areas to ensure food safety and consumer health.

Zn-doped NiMoO4 enhances the performance of electrode materials in aqueous rechargeable NiZn batteries.

In this work, zinc was introduced to prepare Ni1-xZnxMoO4 (0 ≤ x ≤ 1) nanoflake electrodes to increase the energy density and improve the cycling stability for a wider range of applications of aqueous rechargeable nickel-zinc (NiZn) batteries. This was achieved using a facile hydrothermal method followed by thermal annealing, which can be easily scaled up for mass production. Owing to the unique nanoflake structures, improved conductivity, and tunable electronic interaction, excellent electrochemical performance with high specific capacitance and reliable cycling stability can be achieved. When the Zn doping is 25%, the Ni0.75Zn0.25MoO4 nanoflake electrode displays a high specific capacitance of 345.84 mA h g-1 (2490 F g-1) at a current density of 1 A g-1 and improved cycling stability at a high current density of 10 A g-1. NiZn cells assembled with Ni0.75Zn0.25MoO4 nanoflake electrodes and zinc electrodes have a maximum specific capacity of 344.7 mA h g-1 and an energy density of 942.53 W h kg-1. This design strategy for nickel-based electrode materials enables high-performance energy storage and opens up more possibilities for other battery systems in the future.

Ni3S2/Co3S4 with controlled surface electron arrangement for high-performance aqueous energy storage

Ni3S2/Co3S4-Sv is prepared as an electrode material of Ni–Zn battery and supercapacitors. It displays lowered OH− adsorption energy and high DOS value due to combined effect of the heterostructure and sulfur vacancies as reflected from DFT results.

Yttrium doping stabilizes the structure of Ni3(NO3)2(OH)4 cathodes for application in advanced Ni-Zn batteries.

Ni3(NO3)2(OH)4 has a high theoretical specific capacitance, low cost, and environmental friendliness, making it a promising electrode material. Specifically, Ni3(NO3)2(OH)4 electrodes have a larger layer spacing (c = 6.898 Å) than Ni(OH)2 electrodes since NO3- has a much larger ionic radius than OH-. The larger layer spacing stores more electrolyte ions, significantly improving the electrochemical activity of the electrodes. Additionally, the interlayer NO3- can enhance the structural stability of Ni3(NO3)2(OH)4. However, since Ni3(NO3)2(OH)4 has a higher molar mass than Ni(OH)2, it has a lower theoretical specific capacity. Consequently, Ni3(NO3)2(OH)4 has not been used in zinc-based alkaline batteries. Studies showed that doping could enhance the electrochemical performance of electrode materials. Therefore, this study used a simple solvothermal reaction to synthesize yttrium-doped Ni3(NO3)2(OH)4 (Y-Ni3(NO3)2(OH)4), assembling a Y-Ni3(NO3)2(OH)4//Zn battery for electrochemical testing. Y-Ni3(NO3)2(OH)4 served as the cathode in the battery. The analysis of Y-Ni3(NO3)2(OH)4 showed that yttrium (Y) doping increased the specific surface area and pore size of Ni3(NO3)2(OH)4 significantly. The increased specific surface area improved the active material utilization, and the abundant mesopores facilitated OH- transport, substantially enhancing the battery's specific capacity and energy density. Ultimately, the specific discharge capacity of the advanced Y-Ni3(NO3)2(OH)4//Zn battery reached 177.97 mA h g-1 at a current density of 4 A g-1, nearly doubling the capacity of the earlier Ni3(NO3)2(OH)4//Zn battery (103.59 mA h g-1).

Potassium energy storage behavior of nickel–zinc co-doped Prussian blue analogs formed by a chelating-agent-assisted route and its application in a K+-proton hybrid-ion aqueous alkaline battery

Ni3Zn1HCF synthesized through chelating agent assisted route and an aqueous potassium/proton hybrid ions battery was proposed.

Production and characterization of CuNiZnFe2O4 dispersed transformer and kerosene oil based magnetic nanofluids for heat transfer applications

This study produced nanofluids via a two-step method by dispersing copper–nickel–zinc (CuNiZnFe2O4) ferrite nanocomposites in transformer and kerosene oils. A sol–gel auto-combustion approach was adopted to synthesize ferrite nanoparticles. The prepared nanoparticles were analyzed through scanning electron microscopy, photoluminescence spectroscopy, and x-ray diffraction. The measured crystallite size varied between 11 and 13 nm. The SEM images show that the structures of the developed CuNiZn nanoparticles are irregular. The photoluminescence results give a bandgap of 1.91 eV and the emission lines of the nanoparticles. Transient hot wire analysis was performed to determine the thermal conductivity of the base fluid and the prepared nanofluids. It is observed that nanoparticles in the nanofluid enhance the heat transfer rate. It has been proven that CuNiZn/kerosene-based nanofluids have greater thermal conductivity than CuNiZn/transformer oil-based nanofluids. The viscosity of transformer oil-based nanofluids at room temperature is 12.53 mm2 s−1, which decreases to 12.49 mm2 s−1 at 40 °C. Similarly, the viscosity of kerosene-based nanofluids is 1.49 mm2 s−1 at room temperature and 1.16 mm2 s−1 at 40 °C. The sedimentation method revealed that CuNiZn/transformer oil-based nanofluids have greater stability than CuNiZn/kerosene-based nanofluids.

INFLUENCE OF DOPING Zn ON H2 SENSING CHARACTERISTICS OF NICKEL FERRITE NANOPARTICLES

In this paper, the synthesized and testing of H2 gas sensors using nickel zinc ferrite NiFe2O4 and Ni0.5Zn0.5Fe2O4 nanoparticles was shown here. The nickel zinc ferrite nanoparticles were synthesized by chemical co-precipitation combine annealed. Characterization of synthesized powders was made using X-ray diffraction (XRD) and Transmission electron microscopy (TEM) analysis. Nano powder resulting from milling was used to prepare gas sensing elements in pellet form. The gas-sensing properties were studied in presence of hydrogen as test gases. The gas response was found to be strongly influenced by the substitute concentration of Zn. A significant high sensitivity of ~ 90% was found for Zn = 0.5 in presence of 500 ppm H2 at an operating temperature of 250 °C.

Effects of nickel content on the electrochemical performance of nanosized ternary nickel–zinc–cobalt oxide supercapacitors

To improve the electrochemical performance and structural durability of supercapacitors, herein, well-ordered, porous Ni–Zn–Co ternary oxide nanostructures were synthesized by doping Ni to Zn–Co oxide using ultrasonic electrodeposition. Our investigations revealed that Ni–Zn–Co ternary oxide exhibited superior capacity and rate performance when compared to Zn–Co oxide. In particular, the incorporation of 1 mol/L of Ni markedly improved the electrochemical capabilities of the cathode materials. Remarkably, under the influence of ultrasonic power at 500 W, Ni–Zn–Co oxide exhibited a superior mass loading of 6.2 mg/cm2, coupled with exceptional electron transfer efficiency. The growth mechanism and valence composition of Ni–Zn–Co oxides were studied by SEM and XPS analysis. Moreover, electrodes fabricated from Ni–Zn–Co oxide, synthesized via ultrasonic electrodeposition, demonstrated remarkable area capacitance and rate capabilities, achieving an impressive 1.779 F/cm2 at a current density of 3 mA/cm2. Additionally, the supercapacitor incorporating the Ni–Zn–Co oxide electrode exhibited exceptional long-term stability, maintaining a capacity retention rate of 125.2 % over 24,000 cycles in a mild alkaline electrolyte. This study not only contributes to advancing high-performance cathode materials but also offers valuable perspectives on novel techniques for their fabrication.

Designing Architected Nickel Hydroxide Cathodes for Rechargeable Alkaline Nickel–Zinc Batteries

Now that dendrite-suppressing Zn sponge anodes developed at the U.S. Naval Research Laboratory [1] offer a safer route to aqueous batteries that can power a wide range of end uses including electric vehicles, portable electronic devices, and backup energy storage, we need better cathodes. With high rate capability and deep theoretical utilization of the zinc (DOD ≥ 40%) now routine in alkaline electrolytes, storing and delivering more than one electron per metal-centered active material in the cathode is next. We focus on moving the Ni cathode past the 0.8–0.9 electrons per Ni characteristic of fabricating the cathode using β-Ni(OH)2 to tap the extra capacity inherent to α-Ni(OH)2 (theoretical: 1.67 electrons/Ni). Substituting Al3+ into α-Ni(OH)2 stabilizes the alpha phase from conversion to beta phase upon contact with and cycling in aqueous KOH and shifts positive the cell voltage for oxygen evolution (OER), the parasitic charging reaction that affects coulombic efficiency and limits cycle life [2]. We have now redesigned a classic powder composite Ni cathode (carbon black + Ni(OH)2 + binder) into an architected Ni electrode to improve charging efficacy. Using microwave-assisted deposition of Al-substituted α-Ni(OH)2 nanosheets onto a freestanding carbon nanofiber paper electrode wires the active material in 3D to the current-collecting carbon throughout the volume of the electrode. The architected Ni cathodes are tested in alkaline cells versus zinc sponge anodes and demonstrate that architected electron-wiring improves the capacity, rate, and cycle stability of Ni cathodes relative to conventional powder-composite electrodes. Varying the synthetic conditions achieves mass loadings that approach technologically relevant values. The enhanced electrochemical performance of architected Ni cathodes and architected Zn anodes provides a pathway to energy dense, safe, rechargeable Ni–Zn batteries.[1] Parker, J.F.; Chervin, C.N.; Pala, I.R.; Machler, M.; Burz, M.F.; Long, J.W.; Rolison, D.R. Rechargeable Nickel–3D Zinc Batteries: An Energy-Dense, Safer Alternative to Lithium-Ion. Science 2017, 356, 415–418 (10.1126/science.aak9991).[2] Kimmel, S.W.; Hopkins,B.J.; Chervin, C.N.; Skeele, N.L.; Ko, J.S.; DeBlock, R.H.; Long, J.W.; Parker, J.F.; Hudak, B.M.; Stroud, R.M.; Rolison, D.R.;Rhodes, C.P.Capacity and Phase Stability of Metal-Substituted α-Ni(OH)₂ Nanosheets in Aqueous Ni–Zn Batteries. Mater. Adv. 2021, 2, 3060–3074 (10.1039/D1MA00080B).

Electrodeposition of Zn-Cr Alloys: A Comparison with Pure Zinc

The electrodeposition of zinc coatings is one of the most common surface treatments for providing corrosion resistance to metallic components. From the thermodynamic point of view, zinc is located in a sweet spot, with its reduction potential being lower than most other common metals, while at the same time being not too susceptible to atmospheric corrosion; overall these features make zinc the ideal candidate for the electroplating of sacrificial coatings for corrosion protection. Owing it to its low cost and scalability, zinc electroplating has cemented itself as a cornerstone process in a variety of industrial sectors in the last decades. [1]While zinc coatings corrosion resistance has proved to be satisfactory in most cases, it could still be improved to operate even in more aggressive environments. For this purpose, electrodeposition of zinc alloys with transition metals from the iron group (Ni, Co, Fe) has proven to be a successful method to enhance zinc coatings corrosion resistance. In particular, zinc-nickel alloys have found the greater success among them, due to improved corrosion resistance and mechanical properties. [2]Zinc-chromium alloys also present a good opportunity to improve coatings performance, thanks to the passivating effect of Cr. In fact, electrodeposited ZnCr alloys with a Cr content up to 10.4% were found to exhibit a corrosion potential shifted by up 150 mV in the anodic direction with respect to the pure zinc counterpart. [3] This shift led to a significant decrease in the coating dissolution rate but was sufficiently small that the layers could still preserve their sacrificial nature towards the underlying steel.In this work, ZnCr coatings are deposited on low carbon steel from an acidic sulfate formulation containing Cr(III) ions at various concentrations. The properties of ZnCr coatings are explored by varying the most common parameters such as current density, composition, and pH. Furthermore, the resulting coatings are characterized through conventional surface analysis techniques such as SEM, EDS, XRD and XRF. Finally, the corrosion resistance performance of the ZnCr coatings is compared to pure Zn coatings to highlight the benefits of the alloy.Bibliography[1] R. Winand, “Electrodeposition of Zinc and Zinc Alloys,” Mod. Electroplat. Fifth Ed., pp. 285–307, Feb. 2011.[2] N. Lotfi, M. Aliofkhazraei, H. Rahmani, and G. B. Darband, “Zinc–Nickel Alloy Electrodeposition: Characterization, Properties, Multilayers and Composites,” Prot. Met. Phys. Chem. Surfaces, vol. 54, no. 6, pp. 1102–1140, Nov. 2018.[3] V. Chakarova, T. Boiadjieva-Scherzer, D. Kovacheva, H. Kronberger, and M. Monev, “Corrosion behaviour of electrodeposited Zn-Cr alloy coatings,” Corros. Sci., vol. 140, pp. 73–78, Aug. 2018.

Regulated Ni–Zn–Co ferrites: structural, electrical and magnetic properties tailored by co doping

Regulated Ni–Zn–Co ferrites: structural, electrical and magnetic properties tailored by co doping

Effect of Calcination Temperature and Substitution of Erbium on Structural and Optical Properties of Nickel Zinc Ferrite Nanoparticles

A single composition of erbium-doped nickel zinc ferrite Ni0.5Zn0.5Fe1.95Er0.05O4 is synthesized by the sol-gel autocombustion process. The prepared composition was divided into five equal parts. One of the parts was an as-prepared sample, and remaining four other parts were calcinated at 600, 700, 800, and 900 ∘C to investigate the variation in structural and optical properties with the calcination temperature. The structural characterization was performed using XRD and SEM. Optical properties were analyzed using FTIR and UV-Visible spectral data. XRD patterns confirm the spinel cubic crystal structure and the Fd3m space group. The crystallite size was minimum for the as-prepared sample (17.9452 nm), and the crystallite size was maximum for the sample calcinated at 900 ∘C (29.8481 nm). SEM images revealed the grain size in the interval from 55.38 nm to 177.73 nm, and certain nanotubes were formed in the sample calcinated at 800 ∘C. Optical energy band gap was observed in the interval from 5.556 eV to 3.969 eV. All these testifies to the variations in structural and optical properties of Ni0.5Zn0.5Fe1.95Er0.05O4 with the calcination temperature.

Preparation of Zn–Al–Gd-hydrotalcite and performance in zinc-nickel batteries

In this study, Zn–Al-Gd layered double hydroxides (LDHs) were synthesized via a hydrothermal method and investigated as possible negative electrode materials for zinc-nickel batteries. X-ray diffraction analysis and scanning electron microscopy images showed that the as-prepared samples were well crystallized with a hexagonal structure. The electrochemical performance was investigated for Zn–Al-LDHs and Zn–Al-Gd-LDHs with different Zn/Al/Gd molar ratios by cyclic voltammetry, Tafel polarization, electrochemical impedance spectroscopy, galvanostatic charge–discharge measurement, and cycle charge–discharge analysis. The initial discharge capacity reached 416.7 mAh g−1 for the Zn–Al-LDHs electrode and the discharge capacity decreased to 347.3 mAh g−1 after 150 cycles, with a cycle retention rate of 83.34 %. Compared with Zn–Al-LDHs, Zn–Al-Gd-LDHs with different Zn/Al/Gd molar ratios had higher discharge capacities and more stable cycling performance, especially the sample with Zn/Al/Gd = 3:0.8:0.2 (molar ratio). After 150 cycles, the retention rate for the sample with Zn/Al/Gd = 3:0.8:0.2 (molar ratio) was 88.73 %. Zn–Al-Gd-LDHs with a high rate capability can meet the needs of high-storage applications.

Structural and Optical Properties of Sol–Gel-Spin Coating Nanostructured Cadmium Zinc Nickel Phosphate (CZNP) Film and the Current Transport Properties of CZNP/p-Si-Based Diode

In this work, the growth of CdZnNiPO (CZNP) thin films on glass and p-Si substrates using the sol–gel spin coating method was successfully achieved. The structure, and morphology of the CZNP films were analyzed using XRD and FE-SEM. The optical absorbance behavior, energy gap, refractive indices, optical dielectric, optical conductivity, and optical electronegativity of the films were studied using the UV–Vis optical spectroscopy technique. XRD analysis shows that zinc phosphate accommodates cadmium ions by replacing zinc ions in the unit cell, resulting in oxygen vacancies that maintain charge neutrality. Scanning electron microscope images reveal the presence of a highly interconnected and well-organized nano CZNP framework. The optical absorption studies of CZNP films were conducted in the wavelength range of 190–2500 nm. The results show both direct and indirect energy band gaps of 1.69 and 2.89 eV, respectively, were employed in the prepared system. The current–voltage-temperature (I-V-T) characteristics of the CZNP/p-Si junction was analyzed in dark mode. The device transport ideality factor, barrier height, and series resistance were identified.

Multiferroic and magnetic characterization of nickel ferrite- barium titanate nanocomposites

Nickel ferrite (NiFe2O4) samples were prepared by the modified sol–gel technique which is an effective, simple, and rapid synthesis method. Multiferroic composites of nickel ferrite and barium titanate (NiFe2O4-BaTiO3) in the ratio 1:1, 1:2, 2:1 as well as composites of nickel zinc ferrite and barium titanate (Ni1-xZnxFe2O4-BaTiO3) in the ratio 2:1 were synthesized by solid-state reaction method. The formation of nickel ferrite and barium titanate heterogeneous composites was identified using X-ray diffraction analysis (XRD). Magnetic properties were studied using vibrating sample magnetometer at 300 K. The coexistence of ferroelectric and ferromagnetic order confirmed through Magneto-electric (ME) coupling measurement.

Bi3+ doping-enhanced optical and photocatalytic activity with stability of cobalt nickel zinc ferrites for wastewater treatment applications

In this paper, the spinel ferrite nanoparticles Co0.5Ni0.25Zn0.25BixFe2−xO4 (CNZBF) were prepared by citrate-nitrate auto combustion method. Although the substitution process involves a large ion at the expense of a small one, the lattice constant didn't introduce a regular increment behavior with irregular shifts for the peak position at 34.62°, which is related to the (311) plane. Two hypotheses were introduced to justify this behavior. The crystallite size introduced a peculiar behavior in the span of 20.88–14.78 nm with increasing the Bi3+ content. Morphological study via FE-SEM manifested that the CNZBF nanoferrites have agglomerated spherical shapes. Kubelka-Munk function and Tauc's plot for direct allowed transitions were utilized to determine the band gap of all the CNZBF nanoferrites. The doping of Bi tuned the band gap (within 1.55 to 1.25 eV), boosted the light absorption, induced efficient e/h separation, and ensuing charge migration to the Co0.5Ni0.25Zn0.25BixFe2−xO4 surfaces. On account of the CNZBF advantages, a superb removal efficiency (∼96.41 %) of the sample Co0.5Ni0.25Zn0.25Bi0.08Fe1.92O4 via photocatalytic degradation was achieved. After five reusability cycles the nanocatalyst Co0.5Ni0.25Zn0.25Bi0.08Fe1.92O4 introduced 95.08% degradation which demonstrates a trivial efficiency decline of 1.33 % in the photocatalytic activities. These outcomes of excellent photocatalytic activity with the outstanding stability candidate the novel Co0.5Ni0.25Zn0.25Bi0.08Fe1.92O4 for wastewater treatment applications.

NixB/rGO as the cathode for high-performance aqueous alkaline zinc-based battery

Aqueous alkaline zinc batteries (AZBs) exhibit great potential due to their high capacity, high safety and low cost. However, despite these advantages, the lack of high stability and high utilization rate makes the search for high-performance cathode materials a great challenge. Here, an amorphous nickel boride/rGO (NixB/rGO) complex structure was designed. As a result of abundant unsaturated active sites and synergistic electronic effects, amorphous NixB exhibits excellent energy storage properties. As well as having high electrical conductivity, rGO avoids aggregation of NixB nanoparticles, ensuring that NixB/rGO electrodes have a high energy storage capacity. The structure has a strong adhesion between NixB and rGO, which protects its stable structure and extends its life. More importantly, the NixB/rGO//Zn full battery shows remarkable capacity (228.4 mAh/g at 2 A/g), extraordinary cycle durability (93.7% retained after 1000 cycles) and strong energy density 399.7 Wh/kg, when coupled with NixB/rGO cathode. This work will also shed light on other nickel-zinc batteries in order to achieve super durability and capacity.

Structural, optical and magnetic properties of MgFe2O4 and Ni0.5Zn0.5Fe2O4

Spinel ferrite nanoparticles Nickel zinc ferrite (Ni1-xZnxFe2O4 (x = 0.5)) and magnesium ferrite (MgFe2O4) are synthesized by sol-gel auto-combustion and annealed at 1150 °C and 1200 °C respectively. X-ray diffraction (XRD) confirms the presence of a single-phase cubic spinel structure. Lattice parameters crystallite size and density of ferrites are calculated from the XRD data. Surface morphology of the spinel ferrites is studied using Field Emission Scanning Electron Microscopy (FE-SEM). Optical properties such as bandgap, refractive index, extinction coefficient, dielectric constant, and dielectric loss are calculated using UV–Visible spectroscopy. Two absorption bands for each are identified by Fourier Transform Infrared Spectroscopy (FT-IR) peaks, with the lower frequency (400Hz) corresponding to the metal-oxide bond vibrations at the octahedral site and the higher frequency (600Hz) corresponding to the metal-oxide bond vibrations at the tetrahedral sites of the spinel lattice. Magnetic properties are analysed using Vibrating Sample Magnetometer.