Superlattice and Magnetism Directed by the Size and Shape of Nanocrystals

Abstract

With a baton the general directs soldiers and the conductor musicians, and in the nanoworld the rodlike shape also means control, as this form enhances magnetic and coercive properties of crystalline aggregates. Also reported here is a tunable synthetic method, in which the overall shape of the crystal is determined by a balance of kinetically and thermodynamically controlled growth mechanisms. The graphic shows one example of the degree of ordering available in the crystalline through this method.

Preparation of hexagonal close-packed nickel nanoparticles via a thermal decomposition approach using nickel acetate tetrahydrate as a precursor

“…Park et al studied the structural change of Co nanocrystals, and proposed that the formation of hcp structure is a delicate balance between kinetic and ther- modynamic growth regimes. The growth temperature and time were the important parameters for the control of the structure and shape of the Co nanocrystals [39]. In this study we found that the concentration of oleylamine is critical for the formation of hcp Ni.…”

Application of alternative energy forms in catalytic reactor engineering

“…At a particle size above 10 nm, Co NPs demonstrate FM properties at 20 ° C [32] . Minimum sizes for ferromagnetism at 20 ° C are listed Table 2 .…”

Synthesis of Co/MFe2O4 (M=Fe, Mn) core/shell nanocomposite particles

“…However, cobalt-related high moment nanomaterials are chemically and magnetically unstable in ambient conditions due to their rapid oxidation [2]. Many methods have been developed to synthesize monodispersed superparamagnetic Co nanoparticles (NPs) in the size range below 20 nm with high moment density [3][4][5][6][7][8]. But to produce stable aqueous dispersions of Co NPs for biomedical applications has been very challenging.…”