Journal articles: 'Ferrite de nickel'

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Jovalekic, Cedomir, Aleksandar Nikolic, Maja Gruden-Pavlovic, and Miodrag Pavlovic. "Mechanochemical synthesis of stoichiometric nickel and nickel-zinc ferrite powders with Nicolson-Ross analysis of absorption coefficients." Journal of the Serbian Chemical Society 77, no. 4 (2012): 497–505. http://dx.doi.org/10.2298/jsc110302186j.

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The interest in finding new methods for preparation of nickel ferrite (NiFe2O4) and nickel-zinc ferrite (NixZn1-xFe2O4) powders has recently increased, due to the fact that physical and chemical properties of these soft magnetic materials depend strongly on the preparation conditions. In this paper, powder samples of ferrites were obtained by: 1) classic sintering procedure (NixZn1-xFe2O4, x = 0.9) and 2) planetary mill synthesis (both NiFe2O4 and NixZn1-xFe2O4). Mechanochemical reaction leading to the formation of NixZn1-xFe2O4 (x = 1 and 0.9) spinel phase was monitored by SEM, TEM, and XRD. Values of the real and imaginary parts of permittivity and permeability were measured for the obtained nickel and nickel-zinc ferrite samples in the 7-12 GHz frequency range. Based on the obtained results, the EMR absorption coefficients were calculated for all three sample types. It has been concluded that the method of preparation and the final particle size influence the EMR absorption coefficient of nickel and nickel-zinc ferrites.

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Al-Hilli, Muthafer F. "A comparison study of the Structural and magnetic properties of pure Ni metal and NiZnMn ferrite." Iraqi Journal of Physics (IJP) 17, no. 43 (2019): 18–25. http://dx.doi.org/10.30723/ijp.v17i43.418.

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The magnetic properties of a pure Nickel metal and Nickel-Zinc-Manganese ferrites having the chemical formula Ni0.1(Zn0.4Mn0.6)0.9Fe2O4 were studied. The phase formation and crystal structure was studied by using x-ray diffraction which confirmed the formation of pure single spinel cubic phase with space group (Fd3m) in the ferrite. The samples microstructure was studied with scanning electron microstructure and EDX. The magnetic properties of the ferrite and nickel metal were characterized by using a laboratory setup with a magnetic field in the range from 0-500 G. The ferrite showed perfect soft spinel phase behavior while the nickel sample showed higher magnetic loss and coercivity.

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Kruželák, Ján, Andrea Kvasničáková, Michaela Džuganová, Lenka Hašková, Rastislav Dosoudil, and Ivan Hudec. "Curing, Properties and EMI Absorption Shielding of Rubber Composites Based on Ferrites and Carbon Fibres." Polymers 15, no. 4 (2023): 857. http://dx.doi.org/10.3390/polym15040857.

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In this work, magnetic soft ferrites, namely manganese–zinc ferrite, nickel–zinc ferrite and combinations of both fillers, were incorporated into acrylonitrile-butadiene rubber to fabricate composite materials. The total content of ferrites was kept constant—300 phr. The second series of composites was fabricated with a similar composition. Moreover, carbon fibres were incorporated into rubber compounds in constant amount—25 phr. The work was focused on investigation of the fillers on absorption shieling performance of the composites, which was investigated within the frequency range 1–6 GHz. Then, the physical–mechanical properties of the composites were evaluated. The achieved results demonstrated that the absorption shielding efficiency of both composite types increased with increasing proportion of nickel–zinc ferrite, which suggests that nickel–zinc ferrite demonstrated better absorption shielding potential. Higher electrical conductivity and higher permittivity of composites filled with carbon fibres and ferrites resulted in their lower absorption shielding performance. Simultaneously, they absorbed electromagnetic radiation at lower frequencies. On the other hand, carbon fibres reinforced the rubber matrix, and subsequent improvement in physical–mechanical properties was recorded.

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Al-Senani, Ghadah M., Foziah F. Al-Fawzan, Rasmiah S. Almufarij, Omar H. Abd-Elkader, and Nasrallah M. Deraz. "Magnetic Behavior of Virgin and Lithiated NiFe2O4 Nanoparticles." Crystals 13, no. 1 (2022): 69. http://dx.doi.org/10.3390/cryst13010069.

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A series of virgin and lithia-doped Ni ferrites was synthesized using egg-white-mediated combustion. Characterization of the investigated ferrites was performed using several techniques, specifically, X-ray Powder Diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), and High-resolution transmission electron microscopy (HRTEM). XRD-based structural parameters were determined. A closer look at these characteristics reveals that lithia doping enhanced the nickel ferrite lattice constant (a), unit cell volume (V), stress (ε), microstrain (σ), and dislocation density (δ). It also enhanced the separation between magnetic ions (LA and LB), ionic radii (rA, rB), and bond lengths (A-O and B-O) between tetrahedral (A) and octahedral (B) locations. Furthermore, it enhanced the X-ray density (Dx) and crystallite size (d) of random spinel nickel ferrite displaying opposing patterns of behavior. FTIR-based functional groups of random spinel nickel ferrite were determined. HRTEM-based morphological properties of the synthesized ferrite were investigated. These characteristics of NiFe2O4 particles, such as their size, shape, and crystallinity, demonstrate that these manufactured particles are present at the nanoscale and that lithia doping caused shape modification of the particles. Additionally, the prepared ferrite’s surface area and total pore volume marginally increased after being treated with lithia, depending on the visibility of the grain boundaries. Last, but not least, as the dopant content was increased through a variety of methods, the magnetization of virgin nickel ferrite fell with a corresponding increase in coercivity. Uniaxial anisotropy, rather than cubic anisotropy, and antisite and cation excess defects developed in virgin and lithia-doped nickel ferrites because the squareness ratio (Mr/Ms) was less than 0.5. Small squareness values strongly recommend using the assessed ferrites in high-frequency applications.

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Parajuli, D., and K. Samatha. "Structural and cation distribution analysis of Nickel-Copper/Nickel-Magnesium Substituted Lithium Ferrites." BIBECHANA 21, no. 1 (2024): 74–82. http://dx.doi.org/10.3126/bibechana.v21i1.61270.

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Lithium ferrite (Li0.5Fe2.5O4) shows significant promise in electrical and electronic engineering. It possesses a crystal spinel crystal structure denoted as AB2O4, with "A" and "B" representing specific tetrahedral and octahedral lattice sites respectively. Analysis of X-ray diffraction (XRD) patterns aligns well with the JCPDS card (no. 38-0259), confirming the spinel structure with the Fd3m space group. However, an additional peak at 211 in the basic lithium ferrite suggests a subtle Fd3m to the P4132 phase change with a minor secondary hematite phase. Investigating the cation distribution in these ferrites is crucial for further exploration of their magnetic and dielectric properties. These ferrites find widespread applications in microwave technology and magnetic and electric energy storage devices.

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Kolhar, Priyanka, Basavaraja Sannakki, Meenakshi Verma, Prabhakar S.V., Mansoor Alshehri, and Nehad Ali Shah. "Synthesis, Characterization and Investigation of Optical and Electrical Properties of Polyaniline/Nickel Ferrite Composites." Nanomaterials 13, no. 15 (2023): 2223. http://dx.doi.org/10.3390/nano13152223.

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Nickel ferrite nanoparticles are prepared by using a low-temperature self-propagating solution combustion method using urea as fuel. The prepared nickel ferrite nanoparticles were doped with polyaniline in the three different weight ratios of 10%, 30% and 50% by using an in situ polymerization method and by adding ammonium persulfate as an oxidizing agent. The obtained samples were characterized by using XRD, FTIR, SEM and a UV–visible spectrophotometer. XRD examined crystalline peaks of ferrites and amorphous peak of polyaniline and confirmed the formation of the composites. FTIR examined the chemical nature of samples and showed peaks due to polyaniline and the characteristic peaks that were less than 1000 cm−1 wavenumber were due to metal–oxygen bond vibrations of ferrites. AC conductivity increased with frequency in all samples and the highest AC conductivity was seen in polyaniline/nickel ferrite 50%. DC conductivity increased in all samples with the temperature showing the semiconducting nature of the samples. Activation energy was evaluated by using Arrhenius plots and there was a decrease in activation energy with the addition of ferrite content. The UV–visible absorption peaks of polyaniline showed shifting in the composites. The optical direct and indirect band gaps were evaluated by plotting Tauc plots and the values of the optical band gap decreased with addition of ferrite in polyaniline and the Urbach energy increased in the samples with 10%, 30% and 50% polyaniline/nickel ferrite composites. The optical properties of these composites with a low band gap can find applications in devices such as solar cells.

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Nikolaev, Evgeniy, Elena Nikolaevna Lysenko, Anatoly P. Surzhikov, and Anatoliy I. Kupchishin. "Investigation of Magnetic Phase Formation in Nickel-Zinc Ferrites by X-Ray Diffraction and Thermal Analysis." Materials Science Forum 1064 (June 17, 2022): 99–108. http://dx.doi.org/10.4028/p-gedvv4.

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The magnetic spinel phase formation in Ni1-xZnxFe2O4 (x=0.1, 0.3, 0.5) nickel-zinc ferrite synthesized from mechanically activated NiO-ZnO-Fe2O3 mixture was studied by thermomagnetometry method, X-ray diffraction and saturation magnetization analyses. The initial reagents were activated via milling the mixture in a planetary ball mill at 500 and 1000 rpm. The Ni-Zn ferrites were synthesized at 950 °C for 4 hours using the solid-state technology. The correlation between the results obtained using above methods of testing ferrite was revealed. It was found that the magnetic spinel phase concentration in the synthesized samples increases with an increase in the milling energy intensity of mixture. Thus, ferrite obtained from pre-activated at 1000 rpm oxides is characterized by a high concentration of nickel-zinc ferrite in their composition.

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Walters, I., R. Shende, and J. A. Puszynski. "Hydrogen Production from Thermochemical Water-Splitting Using Ferrites Prepared by Solution Combustion Synthesis." Advances in Science and Technology 91 (October 2014): 32–38. http://dx.doi.org/10.4028/www.scientific.net/ast.91.32.

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Currently, there are several methods to produce spinel ferrite powder material such as sol-gel synthesis, self-propagating high-temperature synthesis (SHS), aerosol spray pyrolysis, and solution combustion synthesis (SCS). These methods have been shown to produce nominally phase pure ferrites for use in hydrogen generation by thermochemical water-splitting. Among these methods, the ferrites derived by SCS have not been fully investigated for hydrogen generation from thermochemical water-splitting. SCS, in general, has several advantages such as it being a simple synthesis that can be done relatively quickly and produces materials with high specific surface area. In this study, nickel, zinc, cobalt, and manganese ferrites were synthesized using SCS and analyzed by XRD, BET, and SEM. Each ferrite material was placed inside an Inconel tubular reactor and five consecutive thermochemical cycles to determine hydrogen production. The regeneration and water-splitting temperatures were performed with water-splitting and regeneration temperatures of 900°C and 1100°C, respectively. Nickel ferrite produced significantly higher average hydrogen volume as compared to the other ferrites over the five thermochemical cycles. However, all four ferrites showed a decrease in hydrogen volume generation with increase in consecutive water-splitting cycle, which could be due to the grain growth as observed by BET and SEM analyses.

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V, Nithya, and B. CHIRSABESAN. "Enhancing removal of pollutants from pharmaceutical wastewater using ferrites in Membrane Bioreactor: A promising technology for environmental sustainability." Asian Journal of Chemistry 35, no. 9 (2023): 2225–31. http://dx.doi.org/10.14233/ajchem.2023.28101.

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Industrial wastewater contains various toxic and hazardous pollutants that require effective treatment to meet environmental regulations. In recent years, silver-doped ferrites have gained attention as promising materials for the treatment of industrial wastewater in membrane bioreactor (MBR). In this abstract, we will discuss the potential of silver-doped nickel ferrite (AgNiFe2O4) and silver-doped potassium ferrite (AgKFe2O4) was synthesized by sol-gel technique for the removal of pollutants from industrial wastewater. AgNiFe2O4 and AgKFe2O4 nanoparticles have been found to be effective for the removal of various pollutants, including heavy metals, organic compounds, and dyes, from industrial wastewater. Several studies have reported the successful application of silver-doped ferrites for the treatment of industrial wastewater. X-ray diffraction (XRD) pattern reveals the single phase cubic spinel structure with space group Fd-3m and Scanning electron microscope (SEM) confirmed the surface morphology of the synthesized nanoferrites. The use of AgNiFe2O4 and AgKFe2O4 has been found to significantly reduce the concentration of pollutants in wastewater, making it suitable for safe discharge into the environment. Furthermore, the regeneration of silver-doped ferrites has been found to be simple and cost-effective, making them an attractive alternative to conventional wastewater treatment methods. In conclusion, silver-doped nickel ferrite and silver-doped potassium ferrite have shown great potential for the treatment of pharmaceutical wastewater in MBR technique and ferrite materials make them promising candidates for future wastewater treatment technologies.

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Lesik, Serhii, and Iryna Ivanenko. "Composite NiFe₂O₄ Catalyst for Sodium Borohydride Hydrolysis." ECS Transactions 107, no. 1 (2022): 15433–37. http://dx.doi.org/10.1149/10701.15433ecst.

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Nickel ferrites composite catalysts with the spinel structure were synthesized by the coprecipitation method. Nickel ferrites were deposed on the surface of industrial active carbon. The temperature of final calcination in inert media was 400, 500, and 600°C. The trevorite phase was determined by XR-diffraction; the ratio of Ni to Fe was checked by luminescent analysis, it consisted ~0.61. Crystallites sizes varied in the range from 218 to 252 nm and decreased with an increase in the calcination temperature. It was found that the rate of hydrogen evolution in the reaction of sodium borohydride hydrolysis increases with the reaction temperature increasing; catalysts obtained at lower calcination temperatures showed higher catalytic activity. The maximum Hydrogen Generation Rate (2181 ml×min-1×g-1) was observed for nickel ferrite deposited on the active carbon and calcined at a temperature 400oC; the activation energy of the reaction in the presence of this composite ferrite consisted ~50 kJ×mol-1.

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Bushkova, V. S. "Optical Properties of Ferrite Powders of NixCo1-xFe2O4 System." Фізика і хімія твердого тіла 16, no. 3 (2015): 506–10. http://dx.doi.org/10.15330/pcss.16.3.506-510.

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The aim of this work was to create and study of ferrite nickel-cobalt powders, using sol-gel technology with participation of auto-combustion. It is studied the optical properties of the powders depending on the degree of substitution of cobalt cations on nickel cations. As a result of analysis of the absorption spectra is revealed that for all investigated powders inherent allowed direct transition of electrons from the valence band to the conduction band. It was shown that the optical band gap increases with increasing concentration of nickel cations in the composition of ferrites.

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Kareem, Shaima'a J., Mohammed Naji Al-Aaraji, and Amany Hatem. "Investigation of Microstructure and Physical Properties of Nickel Ferrites, Synthesized via Sol-Gel Method." Solid State Phenomena 341 (March 15, 2023): 57–64. http://dx.doi.org/10.4028/p-88v98w.

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In this paper, studying synthesis and characterization of ferrospinel nickel ferrite. Nickel ferrite is prepared by using the sol-gel method, with a ratio of 2:1 of iron nitrate to nickel nitrate. First the starting material is dissolved in 100 ml of ethylene glycol solution to get the gel and then the gel was dried at 160°C then calcined at 600°C to obtain fine powder, second the nickel ferrite powder is pressed and sintered at 1200°C. To characterize nickel ferrite are used different techniques, such as: XRD is shown high purity, the purity of the nickel ferrite is known and the extent to which the material is affected by the temperatures of calcination and sintering. FT-IR that is shown absorption band between the elements of the components of nickel ferrite appears. The shape of the resulting powder is known through the SEM, the SEM images showed the spherical shape of the nickel ferrite powder, found the particular size of powder at 600°C ranges between405-264 nm and for sample after sintering at 1200°C ranges between589-353 nm, and our Physical characterization test down.

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Tangcharoen, Thanit, Anucha Ruangphanit, Wantana Klysubun, and Wisanu Pecharapa. "Sol-gel Combustion Synthesis and Characterizations of Nanocrystalline Zinc, Nickel and Nickel-Zinc Ferrites." Advanced Materials Research 802 (September 2013): 64–68. http://dx.doi.org/10.4028/www.scientific.net/amr.802.64.

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In this work, X-ray diffraction (XRD), Raman spectroscopy (RAMAN) and vibrating sample magnetometer (VSM) measurements were employed to investigate the crystal structure, chemical bonding and magnetic properties of the nanocrystalline Zinc, Nickel and Nickel-Zinc ferrites (ZnFe2O4, NiFe2O4 and Ni0.5Zn0.5Fe2O4) which were synthesized by sol-gel combustion method. Moreover, the composition of elements and the electronic structure including the cation distribution for all ferrite samples were examined through synchrotron X-ray fluorescence (XRF) and X-ray absorption near-edge structure (XANES) spectra. The overall characterization results indicate that the different amount of zinc and nickel ions in ferrites has crucial effect on their physical, magnetism and the site occupancy distribution of Fe3+ ions.

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Abd-Elkader, Omar H., Nasrallah M. Deraz, and Lotfi Aleya. "Corchorus Olitorius-Mediated Green Synthesis and Characterization of Nickel and Manganese Ferrite Nanoparticles." Symmetry 15, no. 5 (2023): 965. http://dx.doi.org/10.3390/sym15050965.

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Developing a method for preparing Ni and Mn ferrites was the main objective of this study due to the importance of these materials in high-frequency applications. These ferrites were made by assisting combustion with dried leaves of Corchorus olitorius and then heating them to 700 °C. Several methods, including FTIR, XRD, TEM, and SEM/EDX, were used to characterize these ferrites. The thermal behavior, surface and magnetic properties of the as-prepared materials were determined. The results revealed that the method used is cheap, economical, environmentally friendly and makes it easy to produce the studied ferrites. FTIR, XRD, TEM, and SEM/EDX analyses show the formation of nanocrystalline ferrites with brittle, spongy and spinel-type structures, having two main vibration bands located around 400 cm−1 and 600 cm−1. However, TG-DTG results display the thermal behavior of different materials which consisted of unreacted oxides, carbon and the corresponding ferrites in the range of 300 °C to 600 °C. Moreover, complete conversion of the unreacted oxides to the equivalent ferrite was achieved by increasing heat treatment from 600 °C to 1000 °C. Ferrites are heated at 700 °C, which reduces their surface area. The magnetic properties of different ferrites calcined at 700 °C were estimated using the VSM technique. The magnetism of Fe-based materials containing Ni and Mn is 12.189 emu/g and 25.988 emu/g, respectively. Moreover, the squareness and coercivity of Ni ferrite are greater than for Mn ferrite.

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Abdullahi, Umma. "Effects of Alloying Element and Heat Treatment on Mechanical Properties of Alloy Steels." International Journal of Engineering Materials and Manufacture 8, no. 3 (2023): 67–74. http://dx.doi.org/10.26776/ijemm.08.03.2023.02.

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The effects of Cr and Ni on three different types of steel with different carbon ratios under constant conditions such as the welding current 120A, voltage 80V, Diameter 10 mm and angle 60 degree was observed. Nickel percentage of up to 0.147% and Chromium 0.083% contributed to affecting the mechanical properties of the steel. Undissolved carbide particles refine the austenite grain size. In the presence of nickel, chromium carbide is less effective in austenite grain refinement than chromium carbide in absence of nickel at temperature below 975°C. Nickel does not produce any austenite grain refinement but presence of nickel promotes the formation of acicular ferrites. It was also found that Ni and Cr as chromium carbide also refines the ferrite grain size and morphology. Cr as chromium carbide is more effective in refining ferrite grain size than nickel. The microstructure of the base metal as a reference material was analysed before heating to support the results of chemical analysis. Nickel percentage of up to 0.147% and Chromium 0.083%. Molybdenum was 0.03% which contributed to affecting the mechanical properties of the steel.Keyword: Alloy steel, Heat treatment, Chromium, Nickel, Grain size

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Al-Rubaiey, Najem A., Mohammed G. Albrazanjy, Wafaa A. Kadhim, Hassan D. Mohammed, and Mohd Hasbi Ab Rahim. "The Potential of Using Zn_0.6Ni_0.4Fe₂O₄ Nanoparticles as Corrosion Inhibitor for Carbon Steel in Oil Environment." Materials Science Forum 1021 (February 2021): 335–43. http://dx.doi.org/10.4028/www.scientific.net/msf.1021.335.

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Corrosion is one of the serious problems in oil and gas industry. So far, many inhibitors have been used to control or reduce corrosion. Nowadays, nano-materials have been employed as inhibitors as well due to their excellent properties such as high surface area, excellent inhibition efficiency, low cost, and minimum toxicity. In the current work, nano-ferrite materials have been used as inhibitors to reduce the corrosion of carbon steel in oil environment (crude oil obtained from Iraqi Majnoon oil field). The anti-corrosion properties of the nickel and zinc ferrite on carbon steel in Iraqi oil media have been evaluated. The nano materials of nickel Ferrities (NiFe2O4) zinc Ferrities (ZnFe2O4) and Zn-Ni doped Ferities (Zn0.6. Ni0.4Fe2O4) were selected as additive ferrites. It has been found that nano-nickel and zinc ferrites could act as an effective corrosion inhibitor for the metal carbon steel. An average reduction of about 38% in the corrosion rate has been achieved when using Zn-Ni doped Ferities (Zn0.6. Ni0.4Fe2O4) with the crude oil as a corrosive environment.

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Ammani Ammal, V. Beula Shanthi, and N. John Jebarathinam. "Fluid Hyperthermia and Ultrasonic Studies on Nickel Ferrite Magnetic Nanoparticles." Asian Journal of Chemistry 35, no. 6 (2023): 1449–57. http://dx.doi.org/10.14233/ajchem.2023.27577.

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Superparamagnetic nickel ferrite (NiFe2O4) nanoparticles were synthesized by low temperature hydrothermal method using EDTA as templating agent. The synthesized nanoparticles were characterized by FTIR, XRD, FESEM and TEM analysis. The XRD analysis shows the presence of cubic spinel phase with crystallite size of 26.42 nm. The morphology analyzed by FESEM and TEM techniques indicate the presence of cubical shape particles having average particle size of 28.44 nm with no agglomeration. The VSM analysis gives “S” shape curve with zero coercivity and saturation magnetization (Ms) of 30 emu/g indicating the presence of small magnetic particles exhibiting the superparamagnetic behaviour. Nickel ferrite nanofluids were prepared by mixing carrier fluid water with varying amounts of nickel ferrite nanopowder. Zeta potential measurements of dilute solution of nickel ferrite show the formation of stable nickel ferrite nanofluids. Hyperthermia and ultrasonic studies were carried out on various concentrations of nickel ferrite nanofluids. The SAR values and ultrasonic parameters were calculated. Less concentrated nickel ferrite nanofluids quickly attain threshold hyperthermia temperature of 43 °C when exposed to lower applied AC magnetic field of range 5 mT to 20 mT. Ultrasonic studies show at lower concentrations nickel nanoparticles interact with carrier fluid water through cohesive forces mainly hydrogen bonding and keep the particles in an isolated state there by continue to exhibit superparamagnetic characteristics. At higher concentrations, particle-particle interaction predominantly occurs leading to increase in particle size beyond 30 nm, so that the magnetic characteristics of nickel ferrite nanoparticles changes from superparamagnetic to ferromagnetic nature. At low concentrations induction heating occurs through Neel and Brownian relaxation mechanism whereas at high concentrations hysteresis loss mechanism operate to attain the threshold temperature of 43 ºC.

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Li, Jing Jing, Yun Zhao, Han Sheng Li, Qin Wu, and Qing Ze Jiao. "Preparation of Hollow Nickel Ferrite Microspheres and their Magnetic Properties." Advanced Materials Research 1035 (October 2014): 488–91. http://dx.doi.org/10.4028/www.scientific.net/amr.1035.488.

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Hollow nickel ferrite microspheres with a diameter of about 1.5 to 2.5 μm were synthesized using an emulsion-based solvothermal method in combination with calcination at 550°C. The structures and morphologies of the nickel ferrite microspheres were characterized using an X-ray diffractometer, a transmission electron microscopy and a field emission scanning electron microscopy. Magnetization measurement was carried out using a vibrating sample magnetometer at room temperature. The saturation magnetization and coercivity of nickel ferrite microspheres could reach 19.41 emu/g and 202.28 Oe, respectively. Hollow nickel ferrite microspheres might be used as catalysts, magnetic materials and microwave absorbers.

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Bepari, Md Mohar Ali, and Mohiuddin Ahmed. "Effect of Chromium and Nickel Additions on the Transformation Characteristic and Ferrite Grain Size Refinement of Low Carbon Structural Steels Containing 0.13% C." Applied Mechanics and Materials 860 (December 2016): 158–64. http://dx.doi.org/10.4028/www.scientific.net/amm.860.158.

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The effect of small addition of chromium and nickel alone or in combination on the transformation characteristic and ferrite grain size of low carbon (0.13%C) structural steels have been studied by cooling suitable steels at four different cooling rates ranging from 120°C/min to 3.6° C/min from temperatures giving a constant austenite grain size of 37 μm. Radio Frequency generator with control system was used for the heat treatment of the steel samples. Optical microscopy of the heat treated samples was carried out. Ferrite grain size was determined from the fictitious ferrite grain size measured by mean linear intercept method and the volume fraction of pearlite obtained by optical microscopy and point counting. It was found that although the heat treatment of the steels was started from a common austenite grain size, their subsequent ferrite grain size after cooling at the same cooling rate were not the same. Both chromium and nickel enhance the formation of Widmanstatten structure. But chromium is more effective than nickel in the formation of Widmanstatten structure. It was also found that the undissolved particles of chromium carbide (Cr2C) present during austenitizing have no role in determining the ferrite grain size. The precipitating particles of chromium carbide (Cr2C) are excellent ferrite grain size refiners. Nickel refines the ferrite grain size. In presence of nickel, Cr2C precipitates are less effective than Cr2C precipitates in absence of nickel in the refinement of ferrite grain size.

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Lingamdinne, Lakshmi Prasanna, Yu-Lim Choi, Im-Soon Kim, Yoon-Young Chang, Janardhan Reddy Koduru, and Jae-Kyu Yang. "Porous graphene oxide based inverse spinel nickel ferrite nanocomposites for the enhanced adsorption removal of arsenic." RSC Advances 6, no. 77 (2016): 73776–89. http://dx.doi.org/10.1039/c6ra10134h.

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Porous nanocomposites, graphene oxide based-inverse spinel nickel ferrite (GONF) and reduced graphene oxide based-inverse spinel nickel ferrite (rGONF), were prepared by co-precipitation of graphene oxide (GO) with nickel and iron salts at one pot.

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Peelamedu, Ramesh, Craig Grimes, Dinesh Agrawal, Rustum Roy, and Purushotham Yadoji. "Ultralow dielectric constant nickel–zinc ferrites using microwave sintering." Journal of Materials Research 18, no. 10 (2003): 2292–95. http://dx.doi.org/10.1557/jmr.2003.0320.

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Ultralow dielectric constant values were measured on Ni–Zn ferrites prepared using Fe2O3 as a starting material and sintered in a microwave field. Significant differences in microstructure, magnetic, and dielectric properties were observed between microwave-sintered Ni–Zn ferrites prepared using Fe3O4 (T34) and those starting with Fe2O3 (T23) ingredients. Higher magnetization values observed in T23 ferrite are attributed to large grain size, possibly containing abundant domain walls and the presence of fewer Fe2+ ions. The ultralow dielectric constant values observed on T23 ferrites show that this procedure is highly suitable to prepare Ni–Zn ferrites for high-frequency switching applications.

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Ušáková, Mariana, Elemír Ušák, Martin Šoka, and Ján Lokaj. "The influence of selected ions on various characteristics of Nickel-Zinc ferrites." Journal of Electrical Engineering 69, no. 6 (2018): 449–53. http://dx.doi.org/10.2478/jee-2018-0072.

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Abstract One of acknowledged methods remarkably improving structural, magnetic and electrical properties of spinel ferrite systems is the substitution of iron ions by some trivalent ions. In the family of spinel ferrites, thanks to its high saturation magnetization and electrical resistivity as well as low losses, the nickel-zinc ferrite is a very important magnetic material used in many applications in electrical engineering and electronics. The properties of these materials are in general dependent upon chemical composition, method of preparation, stoichiometry, sintering time, temperature as well as the atmosphere, etc. In this study the influence of appropriately selected ions (M = In3+, Nd3+, Dy3+ and Er3+), partly replacing Fe3+, on the microstructure and magnetic properties of spinel ferrite with the composition Ni0.42Zn0.58M0.02Fe1.98O4 fabricated by means of standard ceramic technology was investigated.

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Sarkar, Kakali, Soumya Mukherjee, and Siddhartha Mukherjee. "Structural, electrical and magnetic behaviour of undoped and nickel doped nanocrystalline bismuth ferrite by solution combustion route." Processing and Application of Ceramics 9, no. 1 (2015): 53–60. http://dx.doi.org/10.2298/pac1501053s.

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Multiferroic bismuth ferrite (BFO) and Ni-doped bismuth ferrites, with perovskite structure, were synthesized by chemical route at the temperatures ranging from 500 to 600 ?C in controlled atmosphere. The structural phase analysis of materials was identified by XRD and crystallite size was calculated from the half width measurement of the well defined major XRD diffraction peak. Average crystallite size was calculated by applying Scherrer?s formula and found to have values in the range from 14 to 35 nm. FESEM was used to evaluate the morphology and structural formation of nanocrystallite grains, while EDX confirmed elemental composition including the presence of dopant in the matrix. Dielectric properties and effect of electric field on polarization behaviour were studied for both undoped and Ni-doped BFO. Doping shows a clear change in ferroelectric behaviour. Antiferromagnetic nature of bulk bismuth ferrite transforms to superparamagnetic strong ferroelectric nature for both undoped and nickel doped nanocrystalline bismuth ferrite due to its close dimension of crystallite size with magnetic domains leading to break-down of frustrated spin cycloidal moment. The superparamagnetism behaviour is more pronounced for the nickel doped BFO though magnetic saturation is slightly higher for the undoped nanocrystalline bismuth ferrite.

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Wu, Chun Du, Kun Zheng, and Qing Jie Xie. "The Primary Study of Synthesis and Photocatalytic Activity of ZnO/Nickel-Zinc Ferrite Magnetic Photocatalyst." Advanced Materials Research 955-959 (June 2014): 154–57. http://dx.doi.org/10.4028/www.scientific.net/amr.955-959.154.

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Magnetic photocatalyst ZnO/nickel-zinc ferrite powders were synthesized by two-step method: First ,nickel-zinc ferrite powders were prepared by coprecipitation method and then ZnO /nickel-zinc ferrite composite powders were prepared by the homogeneous precipitation method. The as-prepared sample was characterized by X-ray Diffraction (XRD), and Transmission Electron Microscopy (TEM), the photocatalysis of the catalyst was evaluated with methylene blue as decomposition substance and the photocatalytic activity of the material has been tested on decomposable substrate under visible-light in the magnetic photocatalytic wastewater treatment reactor. The results demonstrate that the magnetic photocatalyst ZnO/nickel-zinc ferrite powders exhibit highly efficient visible-light-driven photocatalytic activity, the degradation rate of methylene blue is 84%.

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Rák, Zs, and D. W. Brenner. "Negative Surface Energies of Nickel Ferrite Nanoparticles under Hydrothermal Conditions." Journal of Nanomaterials 2019 (October 7, 2019): 1–6. http://dx.doi.org/10.1155/2019/5268415.

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The formation of nickel ferrite (NiFe2O4) nanoparticles under hydrothermal conditions has been modeled using a method that combines results of first-principle calculations, elements of aqueous thermochemistry, and experimental free energies of formation. The calculations predict negative formation energies for the (111) surfaces and positive free energies for the formation of bulk nickel ferrite. Based on classical nucleation theory, the combination of the negative surface and positive bulk energies yields thermodynamically stable nickel ferrite nanoparticles with sizes between 30 and 150 nm in the temperature range of 300 to 400 K under alkaline conditions. The surface and bulk energetics as well as the stability of the nickel ferrite nanoparticle as a function of temperature and pH are discussed.

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Gopale, Sanjay, M. R. Patil, R. M. Borade, J. M. Bhandari, and K. M. Jadhav. "Synthesis, Characterizations and Magnetic Properties of Ce-Al Co-Doped Nickel Ferrite Nanoparticles." Advanced Materials Research 1169 (March 18, 2022): 79–85. http://dx.doi.org/10.4028/p-95jpl8.

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Here, we report the synthesis, characterizations and magnetic properties of Ce-Al co-doped nickel ferrite. The samples of pure nickel ferrite ( NiFe2O4 ) and Ce-Al doped nickel ferrite (NiFe1.96Ce0.02Al0.02O4 ) were prepared in nanocrystalline form using sol-gel auto combustion method. X-ray diffraction technique was employed to know the phase purity and for the determination of structural properties. Examination of XRD pattern shows the presence of those reflections which belongs to cubic spinel structure indicating the formation of single phase cubic spinel structure. The lattice constant, X-ray density and other structural parameters were determined from the XRD data and the influence of Al-Ce doping is studied. It is observed from structural studies that the lattice constant and other structural parameters increased. as compared to pure nickel ferrite. The magnetic properties were studied at room temperature using pulsed field hysteresis loop technique. The M-H plot show typical ferrimagnetic behaviour from which the values of saturation magnetization, coercivity and remanence magnetization were obtained. The magnetic data suggests that, Al-Ce co-doping strongly influences the magnetic properties also. The doping of Ce-Al in nickel ferrite leads to canted spin structure. The observed magnetic bahaviour of Ce-Al doped nickel ferrite is explained on the basis of Neel’s and Yafet-Kittel model.

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Janudin, Nurjahirah, Noor Azilah Mohd Kasim, Victor Feizal Knight, et al. "Fabrication of a Nickel Ferrite/Nanocellulose-Based Nanocomposite as an Active Sensing Material for the Detection of Chlorine Gas." Polymers 14, no. 9 (2022): 1906. http://dx.doi.org/10.3390/polym14091906.

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Chlorine gas is extensively utilised in industries as both a disinfectant and for wastewater treatment. It has a pungent and irritating odour that is comparable with that of bleach and can cause serious health issues such as headaches and breathing difficulties. Hence, efficiently, and accurately monitoring chlorine gas is critical to ensure that no undesirable incidents occur. Due to its remarkable characteristics, numerous researchers have explored the potential of ferrite nanoparticles as a sensing material for chlorine gas detection. Among several ferrite nanoparticles, nickel ferrite (NiFe2O4) is extensively studied as an inverse spinel structured magnetic material that may be ideal for sensing applications. However, the magnetic characteristics of NiFe2O4 cause agglomeration, which necessitates the use of a substrate for stabilisation. Therefore, nanocellulose (NC), as a green and eco-friendly substrate, is ideal for stabilising bare nickel ferrite nanoparticles. In a novel experiment, nickel ferrite was loaded onto NC as a substrate using in situ deposition. The structure was confirmed by X-ray Diffraction (XRD) analysis, while elemental composition was verified by Energy dispersive X-ray (EDX) analysis. Gas sensing properties were determined by evaluating sensitivity as a function of various regulating factors, such as the amount of nickel ferrite, gas concentration, repeatability, and reusability. In the evaluation, 0.3 g nickel ferrite showed superior response and sensitivity than those of other samples. The achieved response time was around 40 s, while recovery time was about 50 s. This study demonstrates the potential of a nickel ferrite/nanocellulose-based nanocomposite to efficiently monitor chlorine gas.

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Gu, Jian Jun, Li Hu Liu, Yun Kai Qi, Qin Xu, and Hui Yuan Sun. "Synthesis and Magnetic Characterization of Nickel Ferrite Nanowire Arrays Doped with Manganese." Advanced Materials Research 233-235 (May 2011): 1799–802. http://dx.doi.org/10.4028/www.scientific.net/amr.233-235.1799.

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The spinel ferrite system Ni1-xMnxFe2O4 (x = 0.0, 0.25, 0.5, 0.75) nanowire arrays with an average diameter of about 80 nm, have been synthesized into nanopores of anodic aluminum oxide (AAO) template using the sol–gel technique. X-ray diffraction analysis shows the formation of single-phase nickel manganese ferrites. Scanning electron microscopy and transmission electron microscope images indicate that the nanowire arrays are composed of prolate spheroids with different crystal orientations. Magnetic measurements show that the saturation magnetization (Ms) of nickel ferrite nanowire arrays is lower than that of bulk ones. But the Ms of the samples doped with Mn are greater than that of bulk ones. We do not observe obviously easy magnetization direction of all nanowire arrays. The possible reasons that are responsible for the composition dependence of the properties are discussed.

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VYAS, SHUBANG, NEHA GODHA, RAKSHIT AMETA, and SURESH C. AMETA. "USE OF SOME METAL FERRITES IN THE REDUCTION OF 2,4,6- TRINITROPHENOL." Pollution Research 42, no. 01 (2023): 66–71. http://dx.doi.org/10.53550/pr.2023.v42i01.011.

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The noble-metal Nanocatalyst are widely used, but ferrite-based magnetic catalyst are rarely used. The magnetic copper ferrite, CuFe2 O4 catalyst was synthesized by hydrothermal method and used to reduce 2,4,6-trinitrophenol in presence of sodium borohydride. The copper ferrite was analysed by X-ray diffraction spectroscopy (XRD), Energy-dispersive X-ray spectroscopy (EDX), Scanning Electron Microscopy (SEM) and Fourier transform infrared (FTIR). The reduction of 2,4,6- trinitrophenol was observed in presence of copper ferrite as catalyst and sodium borohydride as the reductant. The conversion of 2, 4, 6-trinitrophenol to 2, 4, 6-triaminophenol was monitored by UV-Visible spectrophotometer. The effect of various parameters such as pH, concentration of nitro compound, and amount of catalyst were studied. The reaction was completed in 8 min in the presence of copper ferrite. It was interesting to note that copper ferrite exhibited higher rate of reduction in present of zinc and nickel ferrites, may due to synergetic effect otherwise they show very slow reduction.

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Stolyar, S. V., O. A. Li, E. D. Nikolaeva, et al. "An Effective Method of Magnetic Hyperthermia Based on the Ferromagnetic Resonance Phenomenon." Физика металлов и металловедение 124, no. 2 (2023): 182–89. http://dx.doi.org/10.31857/s0015323022601490.

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Nickel and cobalt ferrite nanoparticles have been synthesized using the chemical precipitation method; the nanoparticle sizes were found to be 63 ± 22 and 26 ± 4 nm, respectively. The static hysteresis loops and Mössbauer spectra have been measured. It is shown that cobalt ferrite powders are magnetically harder than nickel ferrite powders. Ferromagnetic resonance (FMR) curves have been studied. It is found that the FMR absorption for cobalt ferrite is observed at room temperature and above. The time dependences of the nanoparticle warm-up under FMR conditions have been measured. The maximum temperature changes for nickel ferrite and cobalt ferrite particles are 8 and 11 K, respectively. Using the example of cobalt ferrite powder, the possibility of effectively heating of particles in the FMR mode in their own field without using a DC magnetic field source is shown. The observed effect can be used in magnetic hyperthermia.

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Kotwal, Pinky, Rohit Jasrotia, Himanshi, et al. "A Review on the Synthesis, Properties and Multifunctional Applications of Transition and Rare-Earth Doped Nickel Spinel Ferrite." E3S Web of Conferences 509 (2024): 01011. http://dx.doi.org/10.1051/e3sconf/202450901011.

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Nickel ferrite have gathered a lot of research interest nowadays, because of their unique magnetic and structural traits, which makes appealing for a variety of scientific applications. In recent years, considerable attention has been placed towards the impact of rare-earth and transition elements doping on the magnetic as well as the structural traits of nickel spinel ferrite. This study delivers a concise summary of scientific advancements in this area. It discusses the processes used for fabricating doped nickel spinel ferrite, the influence of different dopants on the material's magnetic and structural traits, and the mechanisms that underlie these effects. The review also highlights the potential applications of doped nickel spinel ferrite in fields such as magnetic data storage, biomedical, and photocatalysis.

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Муслимов, А. Э., А. В. Буташин та В. М. Каневский. "Влияние напряжений на магнитные свойства пленок NiFe-=SUB=-2-=/SUB=-O-=SUB=-4-=/SUB=- и CoFe-=SUB=-2-=/SUB=-O-=SUB=-4-=/SUB=- на сапфире". Письма в журнал технической физики 44, № 16 (2018): 57. http://dx.doi.org/10.21883/pjtf.2018.16.46477.17370.

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AbstractWe have studied the influence of mechanical stresses on the magnetic properties of nickel ferrite (NiFev) and cobalt ferrite (CoFe_2O_4) films deposited on sapphire substrates with a - and c -oriented step terrace nanostructures. It is established that compressive stresses favor enhancement of the coercive field in thin ferrite films in the strain direction. Films of magnetically soft nickel ferrite with a room-temperature coercive field of 32.5 mT were obtained.

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Góes, Júlio C., Sónia D. Figueiró, Karlo David A. Sabóia, et al. "Exploring Dielectric and Magnetic Properties of Ni and Co Ferrites through Biopolymer Composite Films." Magnetochemistry 10, no. 4 (2024): 20. http://dx.doi.org/10.3390/magnetochemistry10040020.

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This study explores the synthesis and characterization of chitosan/gelatine films incorporating nickel ferrite (NiFe2O4) and cobalt ferrite (CoFe2O4) nanoparticles. The magnetic nanoparticles exhibit superparamagnetic behaviour, making them attractive for various applications, including biomedical uses. The X-ray diffraction analysis confirmed the successful synthesis of NiFe2O4 and CoFe2O4 nanoparticles, and the scanning electron micrographs illustrated well-dispersed ferrite nanoparticles within the biopolymer network, despite the formation of some aggregates attributed to magnetic interactions. Magnetization loops revealed lower saturation magnetization values for the composites, attributed to the chitosan/gelatine coating and the dielectric studies, indicating increased dielectric losses in the presence of ferrites, particularly pronounced in the case of NiFe2O4, suggesting interactions at the interface region between the polymer and ferrite particles. The AC conductivity shows almost linear frequency dependence, associated with proton polarization and conduction processes, more significant at higher temperatures for samples with ferrite particles.

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Li, Ming Wei, Cui Ping Liu, and Xiao Mei Gao. "Nickel Ferrite Nanocrystallites Synthesized by Sol-Gel and Coprecipitation Methods: A Comparative Study." Advanced Materials Research 79-82 (August 2009): 305–8. http://dx.doi.org/10.4028/www.scientific.net/amr.79-82.305.

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The microstructures and magnetic properties of nickel ferrite synthesized by coprecipitation and sol–gel methods are comparatively studied. The coprecipitation-derived samples have Fe/Ni ratios differing from their raw materials because of the precipitation washing process. The stoichiometric metal cations (Fe/Ni=2.0) in the xerogel facilitated the nucleation and growth of nickel ferrite nanocrystallites at lower calcination temperature in sol–gel method. The samples consist of nickel ferrite nanocrystallites, and have superparamagnetic properties at room temperature.

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Iacovita, Cristian, Gabriela Fabiola Stiufiuc, Roxana Dudric, et al. "Saturation of Specific Absorption Rate for Soft and Hard Spinel Ferrite Nanoparticles Synthesized by Polyol Process." Magnetochemistry 6, no. 2 (2020): 23. http://dx.doi.org/10.3390/magnetochemistry6020023.

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Spinel ferrite nanoparticles represent a class of magnetic nanoparticles (MNPs) with enormous potential in magnetic hyperthermia. In this study, we investigated the magnetic and heating properties of spinel soft NiFe2O4, MnFe2O4, and hard CoFe2O4 MNPs of comparable sizes (12–14 nm) synthesized by the polyol method. Similar to the hard ferrite, which predominantly is ferromagnetic at room temperature, the soft ferrite MNPs display a non-negligible coercivity (9–11 kA/m) arising from the strong interparticle interactions. The heating capabilities of ferrite MNPs were evaluated in aqueous media at concentrations between 4 and 1 mg/mL under alternating magnetic fields (AMF) amplitude from 5 to 65 kA/m at a constant frequency of 355 kHz. The hyperthermia data revealed that the SAR values deviate from the quadratic dependence on the AMF amplitude in all three cases in disagreement with the Linear Response Theory. Instead, the SAR values display a sigmoidal dependence on the AMF amplitude, with a maximum heating performance measured for the cobalt ferrites (1780 W/gFe+Co), followed by the manganese ferrites (835 W/gFe+Mn), while the nickel ferrites (540 W/gFe+Ni) present the lowest values of SAR. The heating performances of the ferrites are in agreement with their values of coercivity and saturation magnetization.

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36

Liu, Ran, Zhenguo An, Bin Liao, and Jingjie Zhang. "FeNi alloy and nickel ferrite codoped carbon hollow microspheres for high-efficiency microwave absorption." Journal of Materials Chemistry C 10, no. 15 (2022): 6085–97. http://dx.doi.org/10.1039/d2tc00135g.

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Carbon–FeNi alloy–nickel ferrite hollow microspheres with FeNi alloy and nickel ferrite nanoparticle codoped carbon shell were constructed. The products present excellent microwave absorption performance related to the processing condition.

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37

Randhawa, B. S., and R. Singh. "Preparation of Nickel Ferrite from thermolysis of Nickel Hexa(Formato)-Ferrate(III)Hexahydrate." Le Journal de Physique IV 07, no. C1 (1997): C1–89—C1–90. http://dx.doi.org/10.1051/jp4:1997125.

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38

Kolekar, Ravikumar, Suresh Baburao Kapatkar, and Shridhar Narasinhmurthy Mathad. "Synthesis and Characterization of Co0.8-x Nix Zn0.2 Fe2O4 Ferrites by Williamson–Hall and Size–Strain Plot Methods." Acta Chemica Iasi 27, no. 1 (2019): 73–86. http://dx.doi.org/10.2478/achi-2019-0006.

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Abstract The Co-Zn ferrite (x=0.00) and Nickel doped Co-Zn ferrites (x=0.24) was synthesized by low cost solid state reaction method and characterized by XRD technique. The X-ray diffraction results for the samples showed the formation of single phase cubic spinel. The lattice constant and particle size for Co-Zn ferrite(x=0.00) is found to be 8.3465 Å and 26.72 nm and for Nickel doped (x=0.24) it is 8.3440 Å and 24.21nm. Micro strain (ε), Dislocation density(ρD), Hopping lengths (LA and LB), Bond lengths (A - O and B-O), Ionic radii (rA and rB), Texture coefficients (Thkl) and Standard deviation (σ) are also reported. The particle size is confirmed by scanning electron microscope (SEM). The Williamson-Hall plot and stress-strain plot also employed to understand the mechanical properties of materials.

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Abdelwahab, Abdalla, Francisco Carrasco-Marín, and Agustín F. Pérez-Cadenas. "Carbon Xerogels Hydrothermally Doped with Bimetal Oxides for Oxygen Reduction Reaction." Materials 12, no. 15 (2019): 2446. http://dx.doi.org/10.3390/ma12152446.

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A total of two carbon xerogels doped with cobalt and nickel were prepared by the sol–gel method. The obtained carbon xerogels underwent further surface modification with three binary metal oxides namely: nickel cobaltite, nickel ferrite, and cobalt ferrite through the hydrothermal method. The mesopore volumes of these materials ranged between 0.24 and 0.40 cm3/g. Moreover, there was a morphology transformation for the carbon xerogels doped with nickel cobaltite, which is in the form of nano-needles after the hydrothermal process. Whereas the carbon xerogels doped with nickel ferrite and cobalt ferrite maintained the normal carbon xerogel structure after the hydrothermal process. The prepared materials were tested as electrocatalysts for oxygen reduction reaction using 0.1 M KOH. Among the prepared carbon xerogels cobalt-doped carbon xerogel had better electrocatalytic performance than the nickel-doped ones. Moreover, the carbon xerogels doped with nickel cobaltite showed excellent activity for oxygen reduction reaction due to mesoporosity development. NiCo2O4/Co-CX showed to be the best electrocatalyst of all the prepared electrocatalysts for oxygen reduction reaction application, exhibiting the highest electrocatalytic activity, lowest onset potential Eonset of −0.06 V, and the lowest equivalent series resistance (ESR) of 2.74 Ω.

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Wang, Yan, Ying Huang, and Qiu Fen Wang. "The Preparation and Electromagnetic Properties of Nickel-Zinc Ferrite Thin Films." Advanced Materials Research 287-290 (July 2011): 2294–97. http://dx.doi.org/10.4028/www.scientific.net/amr.287-290.2294.

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Compared polyvinyl alcohol with citric acid as complexing agent, nanocrystalline nickel-zinc ferrite thin films were prepared by sol-gel method and dip-coating process under different temperature. The phase composition, morphology, magnetic properties and electromagnetic properties of nanocrystalline nickel-zinc ferrite thin films were studied by X-ray diffractometer (XRD), field emission scanning electron microscope (FESEM), vibrating sample magnetometer (VSM) and vector network analyzer. The results show polyvinyl alcohol is the proper complexing agent for the preparation of nanocrystalline nickel-zinc ferrite thin films, which is stacked with sheet crystals and average diameter of about 20nm. The maximum saturation magnetization, the remanence magnetization and the coercivity of prepared nickel-zinc ferrite thin films are 39.38 emu/g, 11.47emu/g and 182.82 Oe, respectively. Through studying the microwave-absorbing properties of thin films, the maximal absorption quantity is determined at 9.2 GHz.

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Astafyev, Alexandr, Evgeniy Nikolaev, Elena Lysenko, and Anatoly P. Surzhikov. "X-Ray and Thermogravimetric Analyzes of Mechanically Activated Nickel Ferrites." Materials Science Forum 970 (September 2019): 17–23. http://dx.doi.org/10.4028/www.scientific.net/msf.970.17.

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This article shows a study of the effect of mechanical activation of the initial mixture of reagents NiO and Fe2O3 at different speeds of grinding bowl rotation on synthesis of nickel ferrite. Nickel ferrite was produced by the solid-phase synthesis at a temperature of 900 °C for 240 minutes. The obtained ferrite samples were investigated by thermal gravimetric and X-ray phase analysis. The Curie temperature values are obtained, as well as the magnitude of the change of detected instrument weight at the magnetic phase transition (ferromagnetic-paramagnetic) of nickel ferrite using thermal gravimetric curves (TG/DTG) with applied external magnetic field. Increasing of the homogeneity degree of ferrite materials with an increase in the mechanical activation rate is shown based on the data of X-ray phase analysis. The experimental results obtained from thermal, magnetic, and X-ray analyzes were compared.

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Shedam, Rakesh M., Priyanka P. Kashid, Shridhar N. Mathad, Rahul B. Deshmukh, Mahadev R. Shedam, and Ashok B. Gadkari. "Ferrites gas sensors: A Review." Physics and Chemistry of Solid State 23, no. 3 (2022): 626–40. http://dx.doi.org/10.15330/pcss.23.3.626-640.

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Gas sensors that are highly sensitive, stable, and selective are increasingly in demand to detect toxic gases. As a result of the need to monitor concentrations of these gases, humans, animals, and the environment are all protected. Metal ferrites (AFe2O3, where A is a metal) are a major factor in this field. The development of ferrite gas sensors has made remarkable advances in the detection of toxic gases from vehicle exhaust, biological hazards, environmental monitoring, and pollution monitoring over the last decade. It is important for ferrite gas sensors to consider parameters like phase formation, crystallite size, particle size, grain size, dopants, surface area, sensitivity, selectivity, operating temperature, gas concentration, response time, and recovery time. There are various materials for gas sensing use such as carbon monoxide (CO), carbon dioxide (CO2), methane (CH4), ethyl alcohol (C2H5OH), hydrogen sulfide (H2S), C2H5COOH, oxygen (O2), hydrogen (H2), chlorine (Cl2), NH3, C4H10, CH3COOH, gasoline, acetylene, petrol, and liquefied petroleum gas (LPG). Various methods are used to prepare ferrite gas sensors. Additionally, a brief description is provided of the various methods employed for synthesizing ferrite gas sensors. A comprehensive survey of ferrites as gas sensors, such as nickel, copper, zinc, cadmium, cobalt, magnesium, manganese, and multi-component ferrites, prepared by various methods.

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Klumdoung, Pattarinee, Anuwat Hassadee, and Piyapong Pankaew. "Effect of Nickel Ferrite Addition on Characteristics of Nanostructured Nickel Ferrite/Hydroxyapatite Ceramic." Materials Today: Proceedings 17 (2019): 1752–60. http://dx.doi.org/10.1016/j.matpr.2019.06.207.

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Kant, Surya, and H. S. Dosanjh. "UV-Vis adsorption studies of Nickel-Cobalt ferrite developed by combustion method." Journal of Physics: Conference Series 2267, no. 1 (2022): 012086. http://dx.doi.org/10.1088/1742-6596/2267/1/012086.

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Abstract Present work deals with the synthesis of magnetic Nickel-Cobalt spinel ferrite [Ni0.5Co0.5Fe2O4] nanoparticles using combustion method, and adsorption of different dyes using synthesized ferrite material. Synthesized ferrite material has been characterized by using FTIR spectroscopy. Nickel-Cobalt ferrite material has worked very efficiently as an adsorbent and can absorb different dyes from their aqueous solutions. Its magnetic nature gives a fair chance to extract it back from the solutions, by applying magnetic field. Extracted ferrite materials don’t lose its potency to adsorb. Hence, it can be used in number of wastewater treatment cycles. Adsorption capacity and reusability of these ferrite materials make them suitable for future alternate adsorbents in the field of wastewater treatment.

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Şabikoğlu, İsrafil, and Levent Paralı. "FTIR and VSM properties of samarium-doped nickel ferrite." Functional Materials Letters 07, no. 04 (2014): 1450046. http://dx.doi.org/10.1142/s1793604714500465.

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Nickel Ferrite ( NiFe 2 O 4) doped with Samarium (Sm) (0.2, 0.3, 0.4, 0.5 mol.%) was prepared by the conventional solid-state reaction. The crystal structure, surface morphology, infrared spectrum of absorption, and magnetic properties of samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, and vibrating sample magnetometer (VSM). XRD patterns were indexed with inverse spinel cubic phase with the space group of Fd-3m of nickel ferrite. The average grain size was about 5–10 μm. FTIR spectral study on the NiFe 2 O 4 ferrite phase was recorded between 350 cm-1 and 4000 cm-1. Two fundamental absorption bands of the ferrites were appeared at 450 cm-1 and 1000 cm-1 characteristic of metal vibrations. VSM measurements show that the NiFe 2 O 4 doped with Sm 0.3% has the highest value of saturation magnetization. It is also easily demagnetized due to the low value of coercivity field it has. Both NiFe 2 O 4 doped with Sm 0.2 mol.% and 0.4 mol.% materials have same values of coercivity field. However, NiFe 2 O 4 doped with Sm 0.4 mol.% material has the comparatively high value of saturation magnetization than NiFe 2 O 4 doped with Sm 0.2%, also this material was hardly demagnetized, and has highest coercivity field.

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Menezes, P. C. F., Taciana Regina de Gouveia Silva, Ana Cristina Figueiredo de Melo Costa, and Edcleide Maria Araújo. "Preparation and Characterization of Composite of Polyamide 6/Nickel Ferrite." Materials Science Forum 727-728 (August 2012): 609–13. http://dx.doi.org/10.4028/www.scientific.net/msf.727-728.609.

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The research in composites attempt to predict the physico-chemical and mechanical a given mixture of materials. In this work, a composite was produced using as the polyamide 6 matrix and how the burden of nickel ferrite was incorporated as powders calcined at 1200°C and concentration of 50 wt.%. This mixture was compacted in a hydraulic press with heating and characterized by XRD, SEM and TG. XRD results showed the characteristic peaks of polyamide 6 and ferrite. SEM results showed a good dispersion of nickel ferrite loading in the matrix, the presence of larger clusters and evenly distributed load for the composite calcined at 1200 ° C. TG curves showed that the addition of loading of calcined nickel ferrite promoted an increase in thermal stability of the composite compared to pure polyamide.

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Birmule, P. R., A. S. Chavan, B. V. Jadhav, A. S. Burungale, V. B. Helavi-Reddy, and R. P. Patil. "Effect of Nickel Substitution on Structural and Magnetic Properties of Novel Polyol route Synthesized Cobalt Ferrite." Research Journal of Chemistry and Environment 25, no. 8 (2022): 17–22. http://dx.doi.org/10.25303/258rjce1722.

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Nanocrystalline NixCo1-xFe2O4 (1.0 ≥ x ≥ 0) ferrites were prepared by polyol route. Formation of single phase cubic spinel structure for all the compositions was confirmed from their X-ray diffraction patterns. These ferrite samples existed as crystalline nanoparticles of about 10-20 nm size as observed from Transmission Electron Microscopy technique. The magnetic studies indicated that, the ferrimagnetic behavior increases with nickel substitution.

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Opalenko, A. A., A. I. Firov, A. B. Korshak, and L. G. Antoshina. "Investigation of magnetic phase transitions in diluted ferrites: Nickel ferrite." Moscow University Physics Bulletin 65, no. 5 (2010): 417–20. http://dx.doi.org/10.3103/s0027134910050152.

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Pal, M., D. Das, S. N. Chintalapudi, and D. Chakravorty. "Preparation of nanocomposites containing iron and nickel–zinc ferrite." Journal of Materials Research 15, no. 3 (2000): 683–88. http://dx.doi.org/10.1557/jmr.2000.0101.

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Composites consisting of nanometer-sized nickel–zinc ferrite and α-iron were prepared by subjecting micrometer-sized ferrite particles to a reduction treatment in the presence of α–Fe2O3. The materials were characterized by x-ray diffraction, electron microscopy, Mossbauer spectroscopy, and magnetization measurements. A wide range of saturation magnetization and coercivity can be obtained by changing the reduction schedule. The reduction process appears to break down the particle size of the precursor powder of nickel–zinc ferrite.

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Ilosvai, Agnes Maria, Damla Dojcsak, Csaba Váradi, et al. "Sonochemical Combined Synthesis of Nickel Ferrite and Cobalt Ferrite Magnetic Nanoparticles and Their Application in Glycan Analysis." International Journal of Molecular Sciences 23, no. 9 (2022): 5081. http://dx.doi.org/10.3390/ijms23095081.

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Abstract:

The combination of the sonochemical activation of Ni(NO3)2 and Co(NO3)2 in the presence of Fe(NO3)3 and polyethylene glycol and consecutive heat treatment of the formed metal hydroxides offers a cheap and efficient method for the preparation of nickel ferrite and cobalt ferrite magnetic nanoparticles, which can be successfully applied in the selective capture of fluorescently derivatized N-glycans from human serum. XRD measurement revealed that, besides the ferrite phase, nickel and cobalt oxides also form during heat treatment. The amount of simple metal oxides can be well controlled by the temperature of the heat treatment, since increasing temperature yielded higher spinel content. For both nickel and cobalt, the best heat treatment temperature was found to be 673 K, where the samples contained 84.1% nickel ferrite, and in the case of cobalt, almost pure (99.6%) cobalt ferrite could be prepared. FT-IR and zeta potential measurements indicated the presence of surface OH groups, which aided in the dispersion of the particles in water and, in addition, can promote the adsorption of polar compounds. The practical applicability of the magnetic nanopowders was demonstrated in the purification of fluorescently derivatized N-glycans (from human serum). Cobalt ferrite was found to be the most effective. Owing to the easy preparation and the simplicity of the magnetic separation the pure cobalt ferrite, magnetic nanoparticles could be efficient tools for the selective enrichment of serum N-glycans in HPLC measurements.

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Journal articles on the topic 'Ferrite de nickel'

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