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Updated: Apr 6, 2026

Fabrication of Magnetic Platforms for Micron-Scale Organization of Interconnected Neurons
Published on: July 14, 2021
Magnetic multi-granule nanoclusters: A model system that exhibits universal size effect of magnetic coercivity
Ji Sung Lee1, Jin Myung Cha2, Ha Young Yoon1
1Department of Materials Science and Engineering, Korea University, 145 Anam-ro, Seongbuk-gu, Seoul 136-713, Korea.
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.
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