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Magnetic multi-granule nanoclusters: A model system that exhibits universal size effect of magnetic coercivity.

ABSTRACT: It is well known that the coercivity of magnetic nanomaterials increases up to a maximum and then decreases to zero with decreasing particle size. However, until now, no single synthesis method has been able to produce magnetic nanoparticles with a wide range of sizes, i.e., from 10 to 500?nm, in order to uncover the coercivity evolution. Here we report the characterization of magnetite (Fe3O4) multi-granule nanoclusters (MGNCs) to demonstrate the transitional behaviour of coercivity. The M-H curves indicate that our samples had a relatively high saturation magnetization (MS) value of ~70?emu/g and that the coercivity (Hc) increased to the maximum value of ~48 Oe until the nanoclusters reached a size of ~120?nm; the coercivity then gradually decreased to zero.

SUBMITTER: Sung Lee J

PROVIDER: S-EPMC4505357 | biostudies-literature | 2015 Jul

REPOSITORIES: biostudies-literature

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Magnetic multi-granule nanoclusters: A model system that exhibits universal size effect of magnetic coercivity.

Sung Lee Ji J Myung Cha Jin J Young Yoon Ha H Lee Jin-Kyu JK Keun Kim Young Y

Scientific reports 20150717

It is well known that the coercivity of magnetic nanomaterials increases up to a maximum and then decreases to zero with decreasing particle size. However, until now, no single synthesis method has been able to produce magnetic nanoparticles with a wide range of sizes, i.e., from 10 to 500 nm, in order to uncover the coercivity evolution. Here we report the characterization of magnetite (Fe3O4) multi-granule nanoclusters (MGNCs) to demonstrate the transitional behaviour of coercivity. The M-H cu ...[more]

PMID: 26183842

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