Journal articles: 'Magnetite Synthesis'

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Roh, Yul, Hee-Dong Jang, and Yongjae Suh. "Microbial Synthesis of Magnetite and Mn-Substituted Magnetite Nanoparticles: Influence of Bacteria and Incubation Temperature." Journal of Nanoscience and Nanotechnology 7, no. 11 (November 1, 2007): 3938–43. http://dx.doi.org/10.1166/jnn.2007.076.

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Microbial synthesis of magnetite and metal (Co, Cr, Ni)-substituted magnetites has only recently been reported. The objective of this study was to examine the influence of Mn ion on the microbial synthesis of magnetite nanoparticles. The reductive biotransformation of an akaganeite (β-FeOOH) or a Mn-substituted (2–20 mol%) akaganeite (Fe1–xMnxOOH) by Shewanella loiha (PV-4, 25 °C) and Thermoanaerobacter ethanolicus (TOR-39, 60 °C) was investigated under anaerobic conditions at circumneutral pH (pH = 7–8). Both bacteria formed magnetite nanoparticles using akaganeite as a magnetite precursor. By comparison of iron minerals formed by PV-4 and TOR-39 using Mn-mixed akaganeite as the precursor, it was shown that PV-4 formed siderite (FeCO3, green rust [Fe2+Fe3+(OH)16CO3·4H2O], and magnetite at 25 °C, whereas TOR-39 formed mainly nm-sized magnetite at 60 °C. The presence of Mn in the magnetite formed by TOR-39 was revealed by energy dispersive X-ray analysis (EDX) is indicative of Mn substitution into magnetite crystals. EDX analysis of iron minerals formed by PV-4 showed that Mn was preferentially concentrated in the siderite and green rust. These results demonstrate that coprecipitated/sorbed Mn induced microbial formation of siderite and green rust by PV-4 at 25 °C, but the synthesis of Mn-substituted magnetite nanoparticles proceeded by TOR-39 at 60 °C. These results indicate that the bacteria have the ability to synthesize magnetite and Mn-substituted magnetite nano-crystals. Microbially facilitated synthesis of magnetite and metal-substituted magnetites at near ambient temperatures may expand the possible use of specialized ferromagnetic nano-particles.

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Roh, Y., H. Vali, T. J. Phelps, and J. W. Moon. "Extracellular Synthesis of Magnetite and Metal-Substituted Magnetite Nanoparticles." Journal of Nanoscience and Nanotechnology 6, no. 11 (November 1, 2006): 3517–20. http://dx.doi.org/10.1166/jnn.2006.17973.

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We have developed a novel microbial process that exploits the ability of Fe(III)-reducing microorganisms to produce copious amounts of extracellular magentites and metal-substituted magnetite nanoparticles. The Fe(III)-reducing bacteria (Theroanaerobacter ethanolicus and Shewanella sp.) have the ability to reduce Fe(III) and various metals in aqueous media and form various sized magnetite and metal-substituted magnetite nano-crystals. The Fe(III)-reducing bacteria formed metal-substituted magnetites using iron oxide plus metals (e.g., Co, Cr, Mn, Ni) under conditions of relatively low temperature (<70 °C), ambient pressure, and pH values near neutral to slightly basic (pH = 6.5 to 9). Precise biological control over activation and regulation of the biosolid-state processes can produce magnetite particles of well-defined size (typically tens of nanometers) and crystallographic morphology, containing selected dopant metals into the magnetite (Fe3−yXyO4) structure (where X = Co, Cr, Mn, Ni). Magnetite yields of up to 20 g/L per day have been observed in 20-L vessels. Water-based ferrofluids were formed with the nanometer sized, magnetite, and metal-substituted biomagnetite particles.

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Kahani, Seyed Abolghasem, and Zahra Yagini. "A Comparison between Chemical Synthesis Magnetite Nanoparticles and Biosynthesis Magnetite." Bioinorganic Chemistry and Applications 2014 (2014): 1–7. http://dx.doi.org/10.1155/2014/384984.

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The preparation of Fe3O4from ferrous salt by air in alkaline aqueous solution at various temperatures was proposed. The synthetic magnetites have different particle size distributions. We studied the properties of the magnetite prepared by chemical methods compared with magnetotactic bacterial nanoparticles. The results show that crystallite size, morphology, and particle size distribution of chemically prepared magnetite at 293 K are similar to biosynthesis of magnetite. The new preparation of Fe3O4helps to explain the mechanism of formation of magnetosomes in magnetotactic bacteria. The products are characterized by X-ray powder diffraction (XRD), infrared (IR) spectra, vibrating sample magnetometry (VSM), and scanning electron microscopy (SEM).

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Rahmayanti, Maya, Sri Juari Santosa, and Sutarno. "Sonochemical Co-Precipitation Synthesis of Gallic Acid-Modified Magnetite." Advanced Materials Research 1101 (April 2015): 286–89. http://dx.doi.org/10.4028/www.scientific.net/amr.1101.286.

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Gallic acid-modified magnetites were synthesized by one and two-step reactions via the newly developed sonochemical co-precipitation method. The two-step reaction included the formation of magnetite powder and mixing the magnetite powder with gallic acid solution, while the one-step reaction did not go through the formation magnetite powder. The obtained gallic acid-modified magnetites were characterized by the Fourier Transform Infrared (FTIR) spectroscopy, the X-Ray Diffraction (XRD) and the Scanning Electron Microscopy (SEM). More over, the magnetic properties were studied by using a Vibrating Sample Magnetometer (VSM). The characterization results showed that there were differences in crystalinity, surface morphology and magnetic properties of products that were formed by one and two-step reactions.

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Agnestisia, Retno. "Synthesis & Characterization of Magnetit (Fe3O4) and Its Applications As Adsorbent Methylene Blue." Jurnal Sains dan Terapan Kimia 11, no. 2 (October 3, 2017): 61. http://dx.doi.org/10.20527/jstk.v11i2.4039.

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Synthesis, characterization and adsorption study of magnetite have beenconducted. Magnetite was synthesized by coprecipitation method. The characterizations of magnetite were carried out with spectroscopy FTIR (Fourier Transform Infrared) and XRD (X-ray diffraction). The adsorption study was conducted using a batch system with the studied adsorption study including optimum pH, optimum contact time and adsorption equilibrium. The results showed that coprecipitation method has succeeded to form magnetite that has magnetism properties. Magnetite can adsorbed methylene blue from aqueous phase, with the maximum adsorption at pH 5 and contact time of 90 minutes.Adsorption of methylene blue by magnetite follows the adsorption pattern of the Langmuir isotherm with the adsorption energy of 25.59 kJ/mol and adsorption capacity of 43.86 mg/g. The results of magnetite synthesis can accelerate the process of separating the adsorbent particles in a methylene blue solution using an external magnetic field.Keywords : magnetite, coprecipitation, adsorption, and methylene blue.

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Mohd Yusoff, Ahmad Huzaifah, Midhat Nabil Ahmad Salimi, and Mohd Faizal Jamlos. "A New XRD Method to Quantitatively Distinguish Non-Stoichiometric Magnetite: Influence of Particle Size and Processing Conditions." Advanced Engineering Forum 26 (February 2018): 41–52. http://dx.doi.org/10.4028/www.scientific.net/aef.26.41.

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Magnetite’s abilities rely on the quantitative phases present in the sample. Magnetite quality can strongly influence several physical properties, such as magnetism, catalytic performance, and Verwey transition. However, differentiation of magnetite and maghemite through the conventional X-ray diffractogram comparison are not relevant for the intermediate phases. In this study, the deviation from the ideal stoichiometric magnetite and the relative quantification of both phases were mathematically achievable through a new XRD technique. Various synthesis conditions were applied to obtain different crystallite sizes, in the range of 9 to 30 nm. Generally, the stoichiometric deviation and maghemite content would be significantly influenced by the final size, whereas system conditions (temperature of solution, agitation rate, and pH of solution) would only have minor significance. In this study, iron oxide nanoparticles prepared using the co-precipitation method was calculated to contain 100% magnetite for particles of 30.26 nm in size, while 100% maghemite was calculated for particles at 9.64 nm.

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Norfolk, Laura, Andrea Rawlings, Jonathan Bramble, Katy Ward, Noel Francis, Rachel Waller, Ashley Bailey, and Sarah Staniland. "Macrofluidic Coaxial Flow Platforms to Produce Tunable Magnetite Nanoparticles: A Study of the Effect of Reaction Conditions and Biomineralisation Protein Mms6." Nanomaterials 9, no. 12 (December 4, 2019): 1729. http://dx.doi.org/10.3390/nano9121729.

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Magnetite nanoparticles’ applicability is growing extensively. However, simple, environmentally-friendly, tunable synthesis of monodispersed iron-oxide nanoparticles is challenging. Continuous flow microfluidic synthesis is promising; however, the microscale results in small yields and clogging. Here we present two simple macrofluidics devices (cast and machined) for precision magnetite nanoparticle synthesis utilizing formation at the interface by diffusion between two laminar flows, removing aforementioned issues. Ferric to total iron was varied between 0.2 (20:80 Fe3+:Fe2+) and 0.7 (70:30 Fe3+:Fe2+). X-ray diffraction shows magnetite in fractions from 0.2–0.6, with iron-oxide impurities in 0.7, 0.2 and 0.3 samples and magnetic susceptibility increases with increasing ferric content to 0.6, in agreement with each other and batch synthesis. Remarkably, size is tuned (between 20.5 nm to 6.5 nm) simply by increasing ferric ions ratio. Previous research shows biomineralisation protein Mms6 directs magnetite synthesis and controls size, but until now has not been attempted in flow. Here we report Mms6 increases magnetism, but no difference in particle size is seen, showing flow reduced the influence of Mms6. The study demonstrates a versatile yet simple platform for the synthesis of a vast range of tunable nanoparticles and ideal to study reaction intermediates and additive effects throughout synthesis.

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Aulia, Maudi. "Synthesis Of Mg/Al Hydrotalsite-Magnetite As CN- Ion Adsorbent On Wastewater Tapioca Industry." Stannum : Jurnal Sains dan Terapan Kimia 3, no. 2 (December 27, 2021): 69–75. http://dx.doi.org/10.33019/jstk.v3i2.2506.

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Cyanide compounds contained in tapioca industrial wastewater are relatively high, so it is necessary to reduce cyanide levels. This study utilizes the hydrotalcite-magnetite ability to adsorption of CN- ions. The composite formation process is carried out by mixing the magnetite phase at the stage of hydrotalcite-magnetite synthesis. The characterization of X-Ray Diffraction (XRD) shows reflection of the magnetite peak of 2θ 21.42°; 30,28°; 33.40°;35.65° and 37°. While the peak of hydrotalocites at an angle of 11.66° ; 23,33° ; 34,80° ; 60,92° ; and 62.21°. This result is supported by ir spectra on hydrotalocytes shown by O-H group at wave number 3441 cm-1, O=C-O at wave numbers 1359 cm-1, M-O and M-OH at wave numbers 964 cm-1, 797 cm-1 and 673 cm-1. Fe-O and Fe-OH absorption from magnetites at wave numbers 892 cm-1, 798 cm-1 and 629 cm-1. 0.4 grams of hydrotalcite-magnetite at 30 minutes of stirring absorbed 0.0490 mg/L of cyanide from tapioca liquid waste solution. The value of adsorption capacity is 0.022 mg/g and the adsorption efficiency is 87.96%. The hydrotalcite-magnetite adsorption method is superior to aerob and anaerobic methods using bacteria in the tapioca industry.

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Hameed, Aneela, Hafiza Mehvish Mushtaq, and Majid Hussain. "Magnetite (Fe3O4) - Synthesis, Functionalization and its Application." International Journal of Food and Allied Sciences 3, no. 2 (May 25, 2018): 64. http://dx.doi.org/10.21620/ijfaas.2017264-75.

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<p>Nanoparticles are smaller than 100nm. Size of particle depends upon the method that is used for synthesis of nanoparticles. Magnetic nanoparticles consist of iron, cobalt and nickel and their chemical compounds. Their safety or toxicity is major concern for use in food. Magnetite, hematite and meghemite are types of magnetic nanoparticles. Magnetite (Fe3O4) common among the magnetic iron oxide nanoparticle that is used in food industry. Magnetite is getting popular due to its super paramagnetic properties and lack of toxicity to humans. Different methods are used to synthesize magnetic nanoparticles. Upon contact with air these particles loses magnetism and mono-dispersibility. To overcome this problem these nanoparticles are coated with natural or synthetic polymers, metals, organic and inorganic substances to create stable and hydrophilic nanostructures. Due to easy separation with magnet these magnetic nanoparticles are used as an affinity probe to remove bacteria from different food samples and have food related applications e.g, protein purification, enzyme immobilization and food analysis. These magnetic nanoparticles also used for removal of heavy metals and used in medical field.</p>

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RED’KO, YANA, OLGA GARANINA, NATALIIA HUDZENKO, and NATALIIA DUDCHENKO. "PHYSICO-CHEMICAL PROPERTIES OF MAGNETITES IN NANOCOMPOSITES ON THE TEXTILE BASES." Fibres and Textiles 29, no. 3 (November 2022): 3–7. http://dx.doi.org/10.15240/tul/008/2022-3-001.

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The article is devoted to investigation of the physico-chemical properties of magnetites in nanocomposites on the textile bases. It studies of the structure and phase composition of nanocomposite materials on the polyamide and viscose textile bases. It is shown that magnetite particles synthesized in textile material with average sizes of 9.4 nm in viscose textile material and 9.7 nm in polyamide textile material. The influence of synthesis conditions on the size of magnetite nanocrystallites in textile material is established.

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Giannouli, Christina. "Magnetite: Synthesis and Characterization." Key Engineering Materials 543 (March 2013): 460–63. http://dx.doi.org/10.4028/www.scientific.net/kem.543.460.

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Magnetite nanopowder is a nanostructured magnetic material which is of great importance due to its electric and magnetic properties at room temperature. There are quite enough methods to produce magnetite. In the present work, four samples of magnetite powder were produced, the first three with the alkaline precipitation method from aqueous solution of mixed Fe (II)/Fe (III) salts, without any surfactants and the last one with the micro emulsion method. The prepared powders have been characterized using transmission electron microscopy, Raman and FT-IR spectroscopy and x-ray diffraction in order the structure and the morphology of magnetite to be examined. The produced magnetite powders have a size range of 10-12±2nm and the chemical composition of magnetite.

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Cabrera, L., S. Gutiérrez, P. Herrasti, and D. Reyman. "Sonoelectrochemical synthesis of magnetite." Physics Procedia 3, no. 1 (January 2010): 89–94. http://dx.doi.org/10.1016/j.phpro.2010.01.013.

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Khachaturov, A. A., E. E. Potapov, S. V. Reznichenko, and A. N. Kovaleva. "Influence of iron ore concentrate (magnetite) on the kinetics of butadiene–styrene rubber-based blend curing in the presence of different accelerators." Fine Chemical Technologies 15, no. 5 (November 14, 2020): 46–53. http://dx.doi.org/10.32362/2410-6593-2020-15-5-46-53.

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Objectives. To investigate the possibility of using a cheaper ingredient, such as magnetite, in the synthesis of rubber compounds based on butadiene–styrene rubber by examining its effect on the process of sulfuric vulcanization of butadiene–styrene rubber in the presence of various accelerators.Methods. The influence of magnetite on the vulcanization kinetics was studied using an Alpha Technologies PRPA 2000 rotorless rheometer. Thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) were performed using a Mettler Toledo TGA/DSC 2 device to evaluate the effect of magnetite on the butadiene–styrene rubber-based vulcanizates’ oxidation.Results. Magnetite was found to affect the kinetics of SBR-1500 butadiene–styrene rubber sulfuric vulcanization in the presence of thiazole-type accelerators (2-MBT, 2-MBS); in contrast, magnetite was inactive in the case of diphenylguanidine, sulfenamide T, and tetramethylthiuram disulfide. The obtained TGA/DSC data showed that magnetite has no significant effect on the butadiene–styrene rubber-based vulcanizates’ oxidation and thermal destruction.Conclusions. The obtained data confirmed magnetite’s capability to act as a butadiene–styrene rubber sulfuric vulcanization activator in the presence of various accelerators. The most significant effect was observed in the presence of thiazole-type accelerators.

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Roh, Y., H. Vali, T. J. Phelps, and J. W. Moon. "Extracellular Synthesis of Magnetite and Metal-Substituted Magnetite Nanoparticles." Journal of Nanoscience and Nanotechnology 6, no. 11 (November 1, 2006): 3517–20. http://dx.doi.org/10.1166/jnn.2006.047.

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Morel, Mauricio, Francisco Martínez, and Edgar Mosquera. "Synthesis and characterization of magnetite nanoparticles from mineral magnetite." Journal of Magnetism and Magnetic Materials 343 (October 2013): 76–81. http://dx.doi.org/10.1016/j.jmmm.2013.04.075.

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Spoială, Angela, Cornelia-Ioana Ilie, Luminița Narcisa Crăciun, Denisa Ficai, Anton Ficai, and Ecaterina Andronescu. "Magnetite-Silica Core/Shell Nanostructures: From Surface Functionalization towards Biomedical Applications—A Review." Applied Sciences 11, no. 22 (November 22, 2021): 11075. http://dx.doi.org/10.3390/app112211075.

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The interconnection of nanotechnology and medicine could lead to improved materials, offering a better quality of life and new opportunities for biomedical applications, moving from research to clinical applications. Magnetite nanoparticles are interesting magnetic nanomaterials because of the property-depending methods chosen for their synthesis. Magnetite nanoparticles can be coated with various materials, resulting in “core/shell” magnetic structures with tunable properties. To synthesize promising materials with promising implications for biomedical applications, the researchers functionalized magnetite nanoparticles with silica and, thanks to the presence of silanol groups, the functionality, biocompatibility, and hydrophilicity were improved. This review highlights the most important synthesis methods for silica-coated with magnetite nanoparticles. From the presented methods, the most used was the Stöber method; there are also other syntheses presented in the review, such as co-precipitation, sol-gel, thermal decomposition, and the hydrothermal method. The second part of the review presents the main applications of magnetite-silica core/shell nanostructures. Magnetite-silica core/shell nanostructures have promising biomedical applications in magnetic resonance imaging (MRI) as a contrast agent, hyperthermia, drug delivery systems, and selective cancer therapy but also in developing magnetic micro devices.

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Rahimah, Rahimah, Ahmad Fadli, Yelmida Yelmida, Nurfajriani Nurfajriani, and Zakwan Zakwan. "Synthesis and Characterization Nanomagnetite by Co-precipitation." Indonesian Journal of Chemical Science and Technology (IJCST) 2, no. 2 (July 12, 2019): 90. http://dx.doi.org/10.24114/ijcst.v2i2.13995.

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Magnetite (Fe3O4) nanoparticles becomes a new innovation that gets attention of biomedicine scientists. Magnetite can be applied to cancer treatment as a drug carrier because it’s good biocompatibility and very low toxicity. The aim of this study was to determine the effect of temperature and retention time on the magnetite particle characteristics prepared by co-precipitation method. The first, FeCl3 and FeCl2 with 2:1 mole ratio were reacted with 10% NH4OH at 40 - 80°C temperatures during 1 – 30 minutes in a beaker glass. Subsequently, the precipitate was separated using filter paper and it dried into air oven at 100°C. The characteristic of obtained magnetite powder were determined using XRD and SEM. From XRD pattern indicates that magnetite formed at all temperatures with crystallite diameter in the range of 7-13 nm. The SEM results indicate the agglomeration of the magnetite particles with size in the range of 1.37 to 1.72 μm. In the other hand, the higher of temperature and retention time will make the agglomeration of the particles become more uniform. The increasing of temperature and the retention time will increase the magnetite crystallinity level.

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Li, Ming Ya, and Xu Dong Sui. "Synthesis and Characterization of Magnetite Particles by Co-Precipitation Method." Key Engineering Materials 512-515 (June 2012): 82–85. http://dx.doi.org/10.4028/www.scientific.net/kem.512-515.82.

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The Fe3O4 nanoparticles with different diameters were prepared by co-precipitation method in this paper. Magnetite particles with different diameters were fabricated by changing the concentration of the reactants and the reaction temperature. The influences of process parameters on the microstructure and properties of magnetic nanopariticles were studied. The obtained samples were characterized by X-ray powder diffraction and scanning electronic microscopy. Besides, vibrating sample magnetmeter was used to characterize the magnetic properties. The results show that all the as-synthesized magnetite nanoparticles are well crystallized and can be indexed into spinel structure. The appearance and magnetism of the particles with different diameter are different from each other. When the ratio of Fe3+ and Fe2+ is 2:1 or 4:3, the product was pure and good crystalline. Furthermore, higher saturation magnetization was obtained in a higher bath temperature.

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Coltro, Monise Cristina Ribeiro Casanova, Warde Antonieta da Fonseca-Zang, Joachim Werner Zang, and Danilo César Silva e. Sousa. "Síntese, caracterização e estabilidade de nanopartículas de magnetita." Latin American Journal of Development 3, no. 4 (August 31, 2021): 2738–49. http://dx.doi.org/10.46814/lajdv3n4-075.

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Nanopartículas de ferro são muito utilizadas em diversas áreas de pesquisa. O elemento químico ferro (Fe), sendo o quarto elemento mais abundante na crosta terrestre, e a substância mineral magnetita, com propriedade magnética, apresentam aplicações nas áreas industrial, ambiental, biomédica e de novas tecnologias. Este trabalho apresenta processo de síntese de nanopartículas partindo-se de sais precursores, bem como a caracterização dos produtos e as rotas para estabilizá-los. Os sais químicos precursores utilizados foram o cloreto férrico (FeCl3) e o sulfato ferroso (FeSO4) na proporção de 2:1, sob agitação por ultrassom e pH ácido. Para formação do precipitado de nanopartículas usou-se solução aquosa de hidróxido de sódio (NaOH) de pH 12. A difratometria de raio-X, mostra a presença de magnetita (Fe3O4) indicada pelos picos característicos de difração em graus 2Ө = 18° (largo), 31° (fino), 36° (bem definido), 43,4°, 45°, 53,6°, 57,7°, 63,3°. A microscopia eletrônica de transmissão mostra a morfologia dos produtos da síntese. Fatores que influenciam a estabilidade das partículas são agitação, o ajuste de pH, condições de secagem. O tamanho médio das nanopartículas de magnetitas é de aproximadamente 15 nm. Iron nanoparticles are widely used in several research areas. The chemical element iron (Fe), being the fourth most abundant element in the earth's crust, and the mineral substance magnetite, with magnetic properties, have applications in industrial, environmental, biomedical, and new technology areas. This work presents the process of synthesis of nanoparticles starting from precursor salts, as well as the characterization of the products and the routes to stabilize them. The precursor chemical salts were ferric chloride (FeCl3) and ferrous sulfate (FeSO4) in a 2:1 ratio, under ultrasound agitation and acidic pH. For the nanoparticles growth was applied aqueous solution of sodium hydroxide (NaOH) at pH 12. X-ray diffraction shows the presence of magnetite (Fe3O4) indicated by characteristic diffraction peaks in degrees 2Ө = 18° (wide), 31° (fine), 36° (well defined), 43.4°, 45°, 53.6°, 57.7°, 63.3°. Scanning electron microscopy shows the morphology of the synthesis products. Factors that influence the stability of the particles are agitation, the pH adjustment, and the conditions of drying. The average size of the magnetite nanoparticles is approximately 15 nm.

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KAZEMZADEH, HAMID, ABOLGHASEM ATAIE, and FERESHTEH RASHCHI. "SYNTHESIS OF MAGNETITE NANO-PARTICLES BY REVERSE CO-PRECIPITATION." International Journal of Modern Physics: Conference Series 05 (January 2012): 160–67. http://dx.doi.org/10.1142/s2010194512001973.

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Magnetite nano-particles have been synthesized by reverse co -precipitation method using iron salts in alkaline medium in the presence of diethylene glycol (DEG). Effect of DEG on the nano-particle characteristics was investigated by XRD, FE-SEM, FTIR and VSM techniques. From XRD results it was concluded that in the presence of DEG the composition of magnetite did not change, however the mean crystallite size reduced from 10 to 5 nm. SEM micrograph showed that DEG decreased the size of spherical magnetite nano-particles from 50 to 20 nm. Fourier transform infrared spectra (FTIR) indicated that the DEG molecules chemisorbed on the magnetite nano-particles. Under the given experimental conditions, the rate of crystallization and growth reduced, which is probably due to the capping of DEG to the magnetite nano-particles. The agglomeration was also decreased which is attributed to the coating of magnetite nano-particles by DEG which prevents the formation of hydrogen bonding between magnetite and water molecules.

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Wojciechowska, Agnieszka, and Zofia Lendzion-Bieluń. "Synthesis and Characterization of Magnetic Nanomaterials with Adsorptive Properties of Arsenic Ions." Molecules 25, no. 18 (September 9, 2020): 4117. http://dx.doi.org/10.3390/molecules25184117.

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A new synthesis method of hybrid Fe3O4/C/TiO2 structures was developed using microwave-assisted coprecipitation. The aim of the study was to examine the effect of the addition of glucose and titanium dioxide on adsorptive properties enabling removal of arsenic ions from the solution. The study involved the synthesis of pure magnetite, magnetite modified with glucose and magnetite modified with glucose and titanium dioxide in magnetite: glucose: titanium dioxide molar ratio 1:0.2:3. Materials were characterized by XRD, FT-IR, and BET methods. Magnetite and titanium dioxide nanoparticles were below 20 nm in size in obtained structures. The specific surface area of pure magnetite was approximately 79 m2/g while that of magnetite modified with titanium dioxide was above 190 m2/g. Obtained materials were examined as adsorbents used for removal As(V) ions from aqueous solutions. Adsorption of arsenic ions by pure magnetite and magnetite modified with titanium dioxide was very high, above 90% (initial concentration 10 mg/L), pH in the range from 2 to 7. The preparation of magnetic adsorbents with a high adsorption capacity of As(V) ions was developed (in the range from 19.34 to 11.83 mg/g). Magnetic properties enable the easy separation of an adsorbent from a solution, following adsorption.

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Bereczk-Tompa, Éva, Ferenc Vonderviszt, Barnabás Horváth, István Szalai, and Mihály Pósfai. "Biotemplated synthesis of magnetic filaments." Nanoscale 9, no. 39 (2017): 15062–69. http://dx.doi.org/10.1039/c7nr04842d.

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With the aim of creating one-dimensional magnetic nanostructures, we genetically engineered flagellar filaments produced by Salmonella bacteria to display iron- or magnetite-binding sites, and used the mutant filaments as templates for both nucleation and attachment of the magnetic iron oxide magnetite.

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Unsoy, Gozde, Ufuk Gunduz, Ovidiu Oprea, Denisa Ficai, Maria Sonmez, Marius Radulescu, Mihaela Alexie, and Anton Ficai. "Magnetite: From Synthesis to Applications." Current Topics in Medicinal Chemistry 15, no. 16 (May 27, 2015): 1622–40. http://dx.doi.org/10.2174/1568026615666150414153928.

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Vernaya, O. I., V. P. Shabatin, and T. I. Shabatina. "Cryochemical Synthesis of Magnetite Nanoparticles." Moscow University Chemistry Bulletin 73, no. 5 (September 2018): 257–59. http://dx.doi.org/10.3103/s0027131418050103.

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Mirabello, Giulia, Jos J. M. Lenders, and Nico A. J. M. Sommerdijk. "Bioinspired synthesis of magnetite nanoparticles." Chemical Society Reviews 45, no. 18 (2016): 5085–106. http://dx.doi.org/10.1039/c6cs00432f.

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Moon, Ji-Won, Yul Roh, and Tommy J. Phelps. "Review: Magnetite Synthesis using NanoFermentation." Economic and Environmental Geology 45, no. 2 (April 28, 2012): 195–204. http://dx.doi.org/10.9719/eeg.2012.45.2.195.

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Özaytekin, İlkay, and Kamil Oflaz. "Synthesis and characterization of high-temperature resistant and thermally conductive magnetic PBI/Fe3O4 nanofibers." High Performance Polymers 32, no. 9 (May 22, 2020): 1031–42. http://dx.doi.org/10.1177/0954008320911985.

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In the present study, magnetite nanoparticles were added to an electrospinning solution of polyvinylidene fluoride (PVDF)/polybenzimidazole (PBI) polymers to prepare PBI/Fe3O4 nanofibers (NFs). The operating voltage of the electrospinning device was set to 15 kV, the distance between the needle and the plate was 10 cm, and the feed rate was set to 0.3 mL h−1. The microstructures of the as-prepared NFs were investigated by Fourier transform infrared spectrophotometry, atomic force microscopy, thermogravimetric analysis, and vibration sample magnetometry. Magnetite-doped PVDF/PBI NFs exhibited superior magnetism and saturation magnetization in the range of 1.5–5 emu g−1. It was observed that the thermal resistance of the fibers increased with the increasing amount of magnetic particles and nanocomposite fiber (NCF) 1 and NCF2 exhibited excellent thermal resistance up to 415°C and 450°C, respectively. The heat conduction coefficient of the fibers was measured at 4, 6, and 8 W. The thermal conductivity of the NFs increased with the increasing amount of magnetite nanoparticles, and the highest thermal conductivity coefficient for NCF2 (1.83 W mK−1) was measured at 4 W.

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Reza Ghorbani, Hamid, Hossein Pazoki, and Ali Shokuhi Rad. "Synthesis of Magnetite Nanoparticles by Biological Technique." Biosciences, Biotechnology Research Asia 14, no. 2 (June 25, 2017): 631–33. http://dx.doi.org/10.13005/bbra/2488.

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ABSTRACT: The development of synthesis routes for oxide nanoparticles is a matter of considerable topical attention. Green synthesis of nanoparticles with the help of microorganisms as reducing agents is an efficient, cost effective, fast and eco-friendly in nature. This paper presents a simple technique to synthesize magnetite (Fe3O4) nanoparticles. In this routine, an aqueous solution of ferrous and ferric salts was mixed with Magnetospirillum and heated for 10 minutes at 70℃. UV–vis absorption spectra, dynamic light scattering (DLS) and transmission electron microscopy (TEM) have been used to illustrate the form process and explain the structure of the magnetite nanoparticles. UV–Vis absorption spectrum showed surface plasmon resonance absorption bands about 240 nm that confirmed magnetite nanoparticles existence. We obtain magnetite nanoparticles of size 42±20 nm after separation and washing procedures by dynamic light scattering (DLS).

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Golabiazar, Roonak, Zagros A. Omar, Rekar N. Ahmad, Shano A. Hasan, and S. Mohammad Sajadi. "Synthesis and characterization of antibacterial magnetite-activated carbon nanoparticles." Journal of Chemical Research 44, no. 1-2 (October 29, 2019): 80–87. http://dx.doi.org/10.1177/1747519819883884.

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Magnetite iron oxide nanoparticles synthesized using the co-precipitation methods were further functionalized with activated carbon. The magnetite-activated carbon nanoparticles were characterized by scanning electron microscopy equipped with energy dispersive X-ray spectroscopy, transmission electron microscopy, X-ray diffraction, Fourier transform infrared spectroscopy, and UV-Vis spectroscopy. X-ray diffraction and Fourier transform infrared confirmed the functionalization of the Fe3O4 nanoparticles with the activated carbon. The X-ray diffraction studies demonstrate that magnetite-activated carbon nanoparticles were indexed into the spinel cubic lattice with a lattice parameter of 0.833 nm and an average particle size of about 14 nm. Various parameters such as dislocation density, microstrain, and surface morphological studies were calculated. However, this work implicated the use of magnetite-activated carbon nanoparticles in antibacterial studies. Further, the antibacterial effect of magnetite-activated carbon nanoparticles was evaluated against three pathogenic bacteria, which showed that the nanoparticles have moderate antibacterial activity against both Gram-positive ( Staphylococcus aureus) and Gram-negative ( Proteus mirabilis and Pseudomonas aureginosa) pathogenic bacterial strains in the presence of different magnetite-activated carbon nanoparticle concentrations at room temperature.

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Anastasova, Elizaveta I., Vladimir Ivanovski, Anna F. Fakhardo, Artem I. Lepeshkin, Suheir Omar, Andrey S. Drozdov, and Vladimir V. Vinogradov. "A pure magnetite hydrogel: synthesis, properties and possible applications." Soft Matter 13, no. 45 (2017): 8651–60. http://dx.doi.org/10.1039/c7sm01702b.

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Dudchenko, N. O. "Synthetic analogues of biogenic magnetite: synthesis and characterization of magnetite nanoparticles." Materialwissenschaft und Werkstofftechnik 42, no. 2 (February 2011): 89–91. http://dx.doi.org/10.1002/mawe.201100737.

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Mohapatra, Sasmita, Nabakumar Pramanik, Sudip K. Ghosh, and Panchanan Pramanik. "Synthesis and Characterization of Ultrafine Poly(vinylalcohol phosphate) Coated Magnetite Nanoparticles." Journal of Nanoscience and Nanotechnology 6, no. 3 (March 1, 2006): 823–29. http://dx.doi.org/10.1166/jnn.2006.117.

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Nanosized magnetite (Fe3O4) particles showing superparamagnetism at room temperature have been prepared by controlled coprecipitation of Fe2+ and Fe3+ in presence of highly hydrophilic poly(vinylalcohol phosphate)(PVAP). The impact of polymer concentration on particle size, size distribution, colloidal stability, and magnetic property has been extensively studied. The aqueous suspension of magnetite, prepared using 1% PVAP solution is stable for four weeks at pH 5–8. X-ray diffractograms show the formation of nanocrystalline inverse spinel phase magnetite. Transmission Electron Microscopy confirmed well dispersed cubic magnetite particles of size of about 5.8 nm. Dynamic Light Scattering measurement shows narrow distribution of hydrodynamic size of particle aggregates. Infrared spectra of samples show strong Fe—O—P bond on the oxide surface. UV-visible studies show aqueous dispersion of magnetite formed by using 1% PVAP solution is stable at least for four weeks without any detoriation of particle size. Magnetization measurements at room temperature show superparamagnetic nature of polymer coated magnetite nanoparticles.

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Cao, Xueli, Baolin Zhang, Fangyuan Zhao, and Lingyun Feng. "Synthesis and Properties of MPEG-Coated Superparamagnetic Magnetite Nanoparticles." Journal of Nanomaterials 2012 (2012): 1–6. http://dx.doi.org/10.1155/2012/607296.

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The magnetite nanoparticles were synthesized by the thermal decomposition of iron(III) acetylacetonate in methoxy polyethylene glycol, which was used as solvent, reducing agent, and modifying agent in the reaction. The morphologies and phase compositions of the nanoparticles were determined by transmission electron microscopy and X-ray diffraction, respectively. The surface coating of the nanoparticles was recognized using Fourier transform infrared spectroscopy. Magnetic properties were measured using superconducting quantum interference device. The zeta potential and hydrodynamic size of the nanoparticles was determined using nanoparticle and zeta potential analyzer. The magnetite nanoparticles show superparamagnetic behavior in 300 K. The negatively charged methoxy polyethylene glycol-coated magnetite nanoparticles in water exhibited longer-time dispersion with small hydrodynamic size than the magnetite nanoparticles synthesized by the thermal decomposition of iron(III) acetylacetonate in polyethylene glycol. The less conjunction between methoxy polyethylene glycol-coated magnetite nanoparticles due to the inert –CH3terminal group may cause their higher stability in water dispersion.

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Khan, Umar Saeed, Abdul Manan, Nasrullah Khan, Amir Mahmood, and Abdur Rahim. "Transformation mechanism of magnetite nanoparticles." Materials Science-Poland 33, no. 2 (June 1, 2015): 278–85. http://dx.doi.org/10.1515/msp-2015-0037.

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AbstractA simple oxidation synthesis route was developed for producing magnetite nanoparticles with controlled size and morphology. Investigation of oxidation process of the produced magnetite nanoparticles (NP) was performed after synthesis under different temperatures. The phase transformation of synthetic magnetite nanoparticles into maghemite and, henceforth, to hematite nanoparticles at different temperatures under dry oxidation has been studied. The natural magnetite particles were directly transformed to hematite particles at comparatively lower temperature, thus, maghemite phase was bypassed. The phase structures, morphologies and particle sizes of the produced magnetic nanoparticles have been investigated by X-ray diffraction (XRD), transmission electron microscopy (TEM), energy dispersive X-ray spectrometry (EDX) and BET surface area analysis.

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Taylor, R. M., B. A. Maher, and P. G. Self. "Magnetite in soils: I. The synthesis of single-domain and superparamagnetic magnetite." Clay Minerals 22, no. 4 (December 1986): 411–22. http://dx.doi.org/10.1180/claymin.1987.022.4.05.

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AbstractA series of experiments has been carried out to investigate the possible formation of magnetite, Fe3O4, under ambient soil-forming conditions. Rapid and easy synthesis of magnetite was achieved through controlled oxidation of Fe2+ solutions at room temperatures and near neutral pH values. The synthetic products were found to range in size between 0·01–0·07 µm (mean diameter) and hence span the theoretical superparamagnetic-single-domain grain-size boundary.

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Santoso, Uripto Trisno, Abdullah, Dwi Rasy Mujiyanti, Dahlena Ariyani, and Joyo Waskito. "Room Temperature Synthesis of Magnetite Particles by an Oil Membrane Layer-Assisted Reverse Co-Precipitation Approach." Advanced Materials Research 1162 (April 2021): 41–46. http://dx.doi.org/10.4028/www.scientific.net/amr.1162.41.

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Reverse co-precipitation (RCP) in ambient atmosphere is one of the strategies to produce magnetite nanoparticles in a rapid, simple, and cost-effective synthesis route without applying temperature surfactants or inert gases. However, RCP of ferrous/ferric blended salt in sodium hydroxide (NaOH) solution in an oxidizing medium produced of maghemite as a dominant phase rather than magnetite because of the oxidation of Fe2+ to Fe3+ happened. Based on this background, an oil membrane layer-assisted reverse co-precipitation approach has been examined to synthesis of magnetite in ambient atmosphere at room temperature. The result showed that although addition of benzene as an oil membrane layer was effective to prevent oxidation of magnetite to maghemite, but the magnetite particle size for the samples from the oil membrane layer-assisted reverse co-precipitation method was much larger than that from a reverse co-precipitation method without addition of oil membrane layer.

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Montiel, Adriana, Edgar Onofre Bustamante, and María Lorenza Escudero. "Synthesis and Electrochemical Characterisation of Magnetite Coatings on Ti6Al4V-ELI." Metals 10, no. 12 (December 5, 2020): 1640. http://dx.doi.org/10.3390/met10121640.

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Titanium alloys have been widely employed in implant materials owing to their biocompatibility. The primary limitation of these materials is their poor performance in applications involving surfaces in mutual contact and under load or relative motion because of their low wear resistance. The aim of this work is to synthesis magnetite coatings on the Ti6Al4V-ELI alloy surface to increase corrosion resistance and to evaluate its electrochemical behaviour. The coatings were obtained using potentiostatic pulse-assisted coprecipitation (PP-CP) on a Ti6Al4V-ELI substrate. The preliminary X-Ray Diffraction (XRD) results indicate the presence of the magnetite coating with 8–10 nm crystal sizes, determined for the (311) plane. Using X-ray photoelectron spectroscopy (XPS), the presence of the magnetite phase on the titanium alloy was observed. Magnetite coating was homogeneous over the full surface and increased the roughness with respect to the substrate. For the corrosion potential behaviour, the Ti6Al4V-ELI showed a modified Ecorr that was less active from the presence of the magnetite coating, and the impedance values were higher than the reference samples without coating. From the polarization curves, the current density of the sample with magnetite was smaller than of bare titanium.

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BALAJ, D., C. SARALA RUBI, and N. G. RENGANATHAN. "Synthesis and Characterization of Super Paramagnetic Magnetite Nanoparticles for Drug Delivery Application." International Journal of Engineering & Technology 7, no. 2.19 (April 17, 2018): 87. http://dx.doi.org/10.14419/ijet.v7i2.19.15055.

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Attractive nanoparticles have been broadly considered on account of their potential applications as complexity operators in attractive reverberation imaging (MRI) of tumors, cell and DNA partition, attractively guided medication conveyance, tumor hyperthermia. Among the attractive oxides, magnetite nanoparticles are most appropriate because of their low danger and great attractive properties which may be used in drug delivery. Magnetite nanoparticles were synthesized using FeCl3 and FeSO4 as precursors and characterized for size and shape using non-contact AFM. The formation of magnetite was confirmed by XRD pattern. The elemental composition of the obtained phase was determined using EDAX. In this work, we are aiming to develop drug loaded biopolymer Magnetite nanoparticles for biomedical application. Our main objective is to synthesize and characterize Magnetite (Fe3O4) nanoparticles.

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Liu, Boyang, Dechang Jia, Haibo Feng, Qingchang Meng, and Yingfeng Shao. "Synthesis and formation mechanism of hollow carbon spheres encapsulating magnetite nanocrystals." Journal of Materials Research 23, no. 7 (July 2008): 1980–86. http://dx.doi.org/10.1557/jmr.2008.0244.

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Hollow carbon spheres encapsulating magnetite nanocrystals were obtained in high-pressure argon at 600 °C followed by hydrolysis of Fe(NH3)2Cl2 in the hollow interiors at room temperature and heat treatment in argon at 450 °C for 2 h. The structure, morphology, and properties of the products were characterized by x-ray diffraction, field-emission scanning electron microscopy, transmission electron microscopy, thermogravimetric analysis, and vibrating sample magnetometry. The hollow carbon spheres have diameters of 1–10 μm and wall thicknesses of hundreds of nanometers; the wt% of magnetite nanocrystals in them is ∼13.2%. Equiaxed magnetite nanocrystals range in size from 15 to 90 nm, while acicular magnetite nanocrystals have diameters of ∼20 nm and lengths of 120–450 nm. The saturation magnetization value of the hollow carbon spheres encapsulating magnetite nanocrystals is 4.29 emu/g.

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Wallyn, Anton, and Vandamme. "Synthesis, Principles, and Properties of Magnetite Nanoparticles for In Vivo Imaging Applications—A Review." Pharmaceutics 11, no. 11 (November 12, 2019): 601. http://dx.doi.org/10.3390/pharmaceutics11110601.

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The current nanotechnology era is marked by the emergence of various magnetic inorganic nanometer-sized colloidal particles. These have been extensively applied and hold an immense potential in biomedical applications including, for example, cancer therapy, drug nanocarriers (NCs), or in targeted delivery systems and diagnosis involving two guided-nanoparticles (NPs) as nanoprobes and contrast agents. Considerable efforts have been devoted to designing iron oxide NPs (IONPs) due to their superparamagnetic (SPM) behavior (SPM IONPs or SPIONs) and their large surface-to-volume area allowing more biocompatibility, stealth, and easy bonding to natural biomolecules thanks to grafted ligands, selective-site moieties, and/or organic and inorganic corona shells. Such nanomagnets with adjustable architecture have been the topic of significant progresses since modular designs enable SPIONs to carry out several functions simultaneously such as local drug delivery with real-time monitoring and imaging of the targeted area. Syntheses of SPIONs and adjustments of their physical and chemical properties have been achieved and paved novel routes for a safe use of those tailored magnetic ferrous nanomaterials. Herein we will emphasis a basic notion about NPs magnetism in order to have a better understanding of SPION assets for biomedical applications, then we mainly focus on magnetite iron oxide owing to its outstanding magnetic properties. The general methods of preparation and typical characteristics of magnetite are reviewed, as well as the major biomedical applications of magnetite.

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Sari, Fajar Indah Puspita. "Sintesis, Karakterisasi Nanopartikel Magnetit, Mg/Al NO3 –Hidrotalsit dan Komposit Magnetit-Hidrotalsit." Jurnal Kimia VALENSI 3, no. 1 (May 31, 2017): 44–49. http://dx.doi.org/10.15408/jkv.v3i1.4526.

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Synthesis and characterization magnetite, Mg/Al NO3- hydrotalcite and magnetite-hydrotalcite have been done. The XRD and FTIR characterization result from third compound is used to assess the conformation of magnetite in the structure of hydrotalcite by comparison of spectra. Obtained that magnetite nanoparticles (10-20 nm) dispersed on octahedral lattice of hydrotalcite. The position investigation of magnetite particles in the hydrotalcite structure is very useful to determining applications of this composite in various fields, especially that involve ion exchange feature from hydrotalcite.DOI: http://dx.doi.org/10.15408/jkv.v0i0.4526

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Rewatkar, Kishor G. "Magnetic Nanoparticles: Synthesis and Properties." Solid State Phenomena 241 (October 2015): 177–201. http://dx.doi.org/10.4028/www.scientific.net/ssp.241.177.

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The discovery of novel materials, processes, and phenomena at the nanoscale and the development of new experimental and theoretical techniques for research provide fresh opportunities for the development of innovative nanosystems and nanostructured materials. Nanomaterials with tailored unique properties have limitless possibilities in materials science. The most widely used synthesis routes for iron oxide nanoparticles are based on precipitation from solution. Most of the nanoparticles available to date have been prepared using chemical route. Physical processes have also been recently developed to produce high quality monodisperse and monocrystalline iron oxide nanoparticles. Magnetite has recently attracted attention because bulk Fe3O4has a high Curie temperature of 850 K and nearly full spin polarization at room temperature, and due to its wide range of applications in almost all branches of science and technology. Clearly, nanoscale magnetite offers potential for creation of novel technology in multiple fields of study. Opportunities for magnetite nanoparticles to be effectively incorporated into environmental contaminant removal and cell separation magnetically guided drug delivery, imaging of tissue and organs, magnetocytolysis, sealing agents (liquid O-rings), dampening and cooling mechanisms in loudspeakers, high gradient magnetic separation (HGMS) techniques and contrasting agents for magnetic resonance imaging (MRI). Advancement of synthesis and stabilization procedures towards production of uniformly sized, dispersed (potentially embedded) magnetite nanoparticles has clearly inspired creative imagination and application in various fields.

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Li, Yingjie, Emanuel Katzmann, Sarah Borg, and Dirk Schüler. "The Periplasmic Nitrate Reductase Nap Is Required for Anaerobic Growth and Involved in Redox Control of Magnetite Biomineralization in Magnetospirillum gryphiswaldense." Journal of Bacteriology 194, no. 18 (June 22, 2012): 4847–56. http://dx.doi.org/10.1128/jb.00903-12.

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ABSTRACTThe magnetosomes of many magnetotactic bacteria consist of membrane-enveloped magnetite crystals, whose synthesis is favored by a low redox potential. However, the cellular redox processes governing the biomineralization of the mixed-valence iron oxide have remained unknown. Here, we show that in the alphaproteobacteriumMagnetospirillum gryphiswaldense, magnetite biomineralization is linked to dissimilatory nitrate reduction. A complete denitrification pathway, including gene functions for nitrate (nap), nitrite (nir), nitric oxide (nor), and nitrous oxide reduction (nos), was identified. TranscriptionalgusAfusions as reporters revealed that except fornap, the highest expression of the denitrification genes coincided with conditions permitting maximum magnetite synthesis. Whereas microaerobic denitrification overlapped with oxygen respiration, nitrate was the only electron acceptor supporting growth in the entire absence of oxygen, and only the deletion ofnapgenes, encoding a periplasmic nitrate reductase, and not deletion ofnorornosgenes, abolished anaerobic growth and also delayed aerobic growth in both nitrate and ammonium media. While loss ofnosZornorCBhad no or relatively weak effects on magnetosome synthesis, deletion ofnapseverely impaired magnetite biomineralization and resulted in fewer, smaller, and irregular crystals during denitrification and also microaerobic respiration, probably by disturbing the proper redox balance required for magnetite synthesis. In contrast to the case for the wild type, biomineralization in Δnapcells was independent of the oxidation state of carbon substrates. Altogether, our data demonstrate that in addition to its essential role in anaerobic respiration, the periplasmic nitrate reductase Nap has a further key function by participating in redox reactions required for magnetite biomineralization.

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Rahmayanti, Maya. "Synthesis of Magnetite Nanoparticles Using The Reverse Co-precipitation Method With NH4OH as Precipitating Agent and Its Stability Test at Various pH." Natural Science: Journal of Science and Technology 9, no. 3 (December 31, 2020): 54–58. http://dx.doi.org/10.22487/25411969.2020.v9.i3.15298.

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In this study, the synthesis of magnetite was carried out through the reversed coprecipitation method with ammonium hydroxide (NH4OH) as precipitating agent. The aim of the study was to obtain the most appropriate moles ratio of Fe(III) and Fe(II) in obtaining the best characteristics of magnetite, considering that Fe (II) was easily oxidized to Fe (III). Characterization of synthesized magnetite was performed using a Fourier Transform Infrared (FTIR) spectrophotometer and X-Ray Diffraction (XRD). The results showed that the moles ratio of Fe (III) and Fe (II) that produced magnetite with high yield, FTIR spectra absorption and diffractogram peaks with high intensity was magnetite synthesized using a ratio of Fe (III) and Fe (II) = 1.5: 1. Yield of magnetite synthesized in this condition was 81%. Based on the stability test, magnetite was stable at pH 2-10.

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Fadli, Ahmad, Amun Amri, Esty Octiana Sari, Sukoco Sukoco, and Deden Saprudin. "The Oriented Attachment Crystal Growth Model in Hydrothermal Synthesis of Magnetite (Fe3O4) Nanoparticles." Journal of Applied Materials and Technology 1, no. 1 (July 18, 2019): 15–19. http://dx.doi.org/10.31258/jamt.1.1.15-19.

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The magnetite nanoparticles (Fe3O4) are very promising nanomaterials to be applied as drug delivery due to their excellent superparamagnetic, biocompatibility and easily modified surface properties. Those properties are influenced by the structure and size of the material which can be controlled by studying the evolution of crystal growth. The purpose of this research is to study the evolution of crystal growth of magnetite nanoparticles in the hydrothermal system and determine the crystal growth kinetics using the Oriented Attachment Growth model. Magnetite nanoparticles were synthesized using a hydrothermal method from FeCl3, citrate, urea and polyethylene glycol at 210˚C for 1 - 12 hours at a various concentration of FeCl3 (0.05 M, 0.10 M, and 0.15 M). The characterizations were conducted by X-ray Diffraction (XRD), Transmission Electron Microscope (TEM), Particle size analyzer (PSA), and Vibrating Sample Magnetometer (VSM). The XRD difractogram indicated that the magnetite was begun to form at 3.5 hours synthesis. The crystallinity and the crystal size of magnetite rose with reaction time. The diameter of magnetite crystals was in the range of 9.4-30 nm. Characterization by TEM showed that the particles were formed from a smaller particles which were then agglomerated. The PSA characterization showed that the distribution of diameter size enlarged with the enhancement of concentrations. VSM result showed that the magnetite nanoparticle has superparamagnetic properties. The magnetite crystal growth can be fitted by the Oriented Attachment Growth model with an error of 29%.

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ZHANG, CAIQUAN, YALI CUI, DIDI, KUNPING YAN, CHAO CHEN, and MINGLI PENG. "SOLVOTHERMAL SYNTHESIS OF UNIFORM MAGNETITE MICROSPHERES." Functional Materials Letters 03, no. 02 (June 2010): 125–29. http://dx.doi.org/10.1142/s179360471000107x.

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Facile procedures to synthesize large quantities of uniform and well dispersed magnetite particles in water were developed through a solvothermal method. Magnetite microspheres were obtained by using FeCl 3 · 6H 2 O , urea and polyethylene glycol as the starting materials in ethylene glycol at 200°C for 8 h. The samples were characterized by using X-ray diffraction, transmission electron microscopy, scanning electron microscopy and vibrating sample magnetometry. Experimental results revealed that the particles were well dispersed with uniform particle size and diameters in the range 260 to 280 nm. The saturation magnetization value was 71.5 emu/g with negligible remanence.

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BASAVAIAH, K., and A. V. PRASADA RAO. "Synthesis of Polystyrenesulfonic Stabilized Magnetite Nanoparticle." Chemical Science Transactions 1, no. 2 (July 13, 2012): 382–86. http://dx.doi.org/10.7598/cst2012.4790.

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Belikov, V. G., and A. G. Kuregyan. "Synthesis of Magnetite Complexes with Drugs." Pharmaceutical Chemistry Journal 38, no. 3 (March 2004): 153–56. http://dx.doi.org/10.1023/b:phac.0000034306.33479.4d.

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Sun, Shouheng, and Hao Zeng. "Size-Controlled Synthesis of Magnetite Nanoparticles." Journal of the American Chemical Society 124, no. 28 (July 2002): 8204–5. http://dx.doi.org/10.1021/ja026501x.

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Pati, S. S., S. Kalyani, V. Mahendran, and John Philip. "Microwave Assisted Synthesis of Magnetite Nanoparticles." Journal of Nanoscience and Nanotechnology 14, no. 8 (August 1, 2014): 5790–97. http://dx.doi.org/10.1166/jnn.2014.8842.

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Journal articles on the topic 'Magnetite Synthesis'

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