An investigation on the behavior of fine-grained magnetite particles as a function of size and surface modification

Zhang, Yi; Ren, Zhiyan; Fu, Yu; Yuan, Xue; Zhai, Ya; Huang, H.; Zhai, Hongru

doi:10.1016/j.jpcs.2008.11.017

Cited by 18 publications

(7 citation statements)

References 17 publications

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“…This impact seems to be larger for materials with larger exchange lengths. This idea fits well to a previous study dealing with magnetite and nickel ferrite, [20] materials with even larger exchange length in the range of 27 nm (magnetite) or 10 nm (nickel ferrite), respectively, [42,43] where especially for magnetite severe differences between fully agglomerated and distributed nanoparticles were found. Unexpectedly, the influence of the concentration is relatively low in most cases.…”

Section: 1% No Trend Valid For All Materials Under Investigation Can ...supporting

confidence: 92%

Micromagnetic Simulations of Nanoparticles with Varying Amount of Agglomeration

Błachowicz

Grzybowski

Ehrmann

2022

Macromolecular Symposia

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Magnetic nanoparticles can be used for medical and other purposes, but can also be integrated in polymeric or other nonmagnetic matrices of diverse shapes, for example, thin‐films or fibers. In the latter case, it may be important how the magnetic nanoparticles are distributed in the matrix, a topic which is often not taken into account when such composites are investigated experimentally or theoretically. Especially for small magnetic nanoparticles of dimensions allowing coherent reversal, the magnetic properties of such polymer/magnet composites can change drastically in the case of agglomerations. Here, a method is suggested to quantify the influence of nanoparticle distributions inside nonmagnetic matrices. By changing the average distance between nanoparticles of varying diameters between highly distributed particles and perfectly packed clusters, different magnetization dynamics can be modeled by micromagnetic simulations. Here, this process is shown for various magnetic materials and diameter distributions of magnetic nano‐spheres and present corresponding micromagnetic simulation results, which underline the importance of taking into account possible magnetic agglomerations in nonmagnetic space.

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Section: 1% No Trend Valid For All Materials Under Investigation Can ...supporting

confidence: 92%

Micromagnetic Simulations of Nanoparticles with Varying Amount of Agglomeration

Błachowicz

Grzybowski

Ehrmann

2022

Macromolecular Symposia

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“…Interestingly, the corresponding nitrate concentrations are therefore much lower than those, usually reported in literature. [ 3,12,28,29,31,32 ] In order to point out a possible correlation, values with a certain relationship to reduction paths therefore serve as starting points for the experiments and receive special attention concerning the interpretation of the results.…”

Section: Theoretical Modelmentioning

confidence: 99%

“…In this respect, a number of investigations can be found which, for example, deal intensively with the influence of the pH value, the type of oxidant, the temperature, or the ions present. [ 3,6,11,12,15–17,28,29,30,31 ] Unfortunately, information about the role of nitrate concentration can rarely be found.…”

Section: Introductionmentioning

confidence: 99%

Oxidative Precipitation as a Versatile Method to Obtain Ferromagnetic Fe₃O₄ Nano‐ and Mesocrystals Adjustable in Morphology and Magnetic Properties

Granath

Löbmann

Mandel

2021

Part & Part Syst Charact

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Oxidative precipitation is a facile synthesis method to obtain ferromagnetic iron oxide nanoparticles from ferrous salts—with unexplored potential. The concentration of base and oxidant alone strongly affects the particle's structure and thus their magnetic properties despite the same material, magnetite (Fe3O4), is obtained when precipitated with potassium hydroxide (KOH) from ferrous sulfate (FeSO4) and treated with potassium nitrate (KNO3) at appropriate temperature. Depending on the potassium hydroxide and potassium nitrate concentrations, it is possible to obtain a series of different types of either single crystals or mesocrystals. The time‐dependent mesocrystal evolution can be revealed via electron microscopy and provides insights into the process of oriented attachment, yielding faceted particles, showing a facet‐dependent reactivity. It is found that it is the nitrate and hydroxide concentration that influences the ligand exchange process and thus the crystallization pathways. The presence of sulfate ions contributes to the mesocrystal evolution as well, as sulfate apparently hinders further crystal fusion, as revealed via infrared spectroscopy. Finally, it is found that nitrite, as one possible and ecologically highly relevant reduction product occurring in nature in context with iron, only evolves if the reaction is quantitative.

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“…Iron oxides (such as ␥-Fe 2 O 3 or Fe 3 O 4 ) have been considered to be ideal candidates for biological applications due to their special magnetic properties, lack of toxicity, and good biocompatibility [20][21][22][23][24][25][26]. Many new nanoparticle labels have been introduced for biomedical applications.…”

Section: Introductionmentioning

confidence: 99%

A simple approach for the synthesis of bifunctional Fe3O4@Gd2O3:Eu3+ core–shell nanocomposites

Peng

Cui

et al. 2012

Journal of Alloys and Compounds

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An investigation on the behavior of fine-grained magnetite particles as a function of size and surface modification

Cited by 18 publications

References 17 publications

Micromagnetic Simulations of Nanoparticles with Varying Amount of Agglomeration

Micromagnetic Simulations of Nanoparticles with Varying Amount of Agglomeration

Oxidative Precipitation as a Versatile Method to Obtain Ferromagnetic Fe₃O₄ Nano‐ and Mesocrystals Adjustable in Morphology and Magnetic Properties

A simple approach for the synthesis of bifunctional Fe3O4@Gd2O3:Eu3+ core–shell nanocomposites

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An investigation on the behavior of fine-grained magnetite particles as a function of size and surface modification

Cited by 18 publications

References 17 publications

Micromagnetic Simulations of Nanoparticles with Varying Amount of Agglomeration

Micromagnetic Simulations of Nanoparticles with Varying Amount of Agglomeration

Oxidative Precipitation as a Versatile Method to Obtain Ferromagnetic Fe3O4 Nano‐ and Mesocrystals Adjustable in Morphology and Magnetic Properties

A simple approach for the synthesis of bifunctional Fe3O4@Gd2O3:Eu3+ core–shell nanocomposites

Contact Info

Product

Resources

About

Oxidative Precipitation as a Versatile Method to Obtain Ferromagnetic Fe₃O₄ Nano‐ and Mesocrystals Adjustable in Morphology and Magnetic Properties