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Compact Ag@Fe3O4 core-shell nanoparticles by means of single-step thermal decomposition reaction.

ABSTRACT: A temperature pause introduced in a simple single-step thermal decomposition of iron, with the presence of silver seeds formed in the same reaction mixture, gives rise to novel compact heterostructures: brick-like Ag@Fe3O4 core-shell nanoparticles. This novel method is relatively easy to implement, and could contribute to overcome the challenge of obtaining a multifunctional heteroparticle in which a noble metal is surrounded by magnetite. Structural analyses of the samples show 4 nm silver nanoparticles wrapped within compact cubic external structures of Fe oxide, with curious rectangular shape. The magnetic properties indicate a near superparamagnetic like behavior with a weak hysteresis at room temperature. The value of the anisotropy involved makes these particles candidates to potential applications in nanomedicine.

SUBMITTER: Brollo ME

PROVIDER: S-EPMC4213770 | biostudies-literature | 2014

REPOSITORIES: biostudies-literature

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Compact Ag@Fe3O4 core-shell nanoparticles by means of single-step thermal decomposition reaction.

Brollo Maria Eugênia F ME López-Ruiz Román R Muraca Diego D Figueroa Santiago J A SJ Pirota Kleber R KR Knobel Marcelo M

Scientific reports 20141030

A temperature pause introduced in a simple single-step thermal decomposition of iron, with the presence of silver seeds formed in the same reaction mixture, gives rise to novel compact heterostructures: brick-like Ag@Fe3O4 core-shell nanoparticles. This novel method is relatively easy to implement, and could contribute to overcome the challenge of obtaining a multifunctional heteroparticle in which a noble metal is surrounded by magnetite. Structural analyses of the samples show 4 nm silver nano ...[more]

PMID: 25354532

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