Iron Oxide-Gold Core-Shell Nanoparticles and Thin-Film Assembly

Journal Article · Wed May 04 04:00:00 EDT 2005 · Journal of Materials Chemistry, 15(18):1821-1832

DOI:https://doi.org/10.1039/b501375e· OSTI ID:15020659

Wang, Lingyan; Luo, Jin; Maye, Mathew M; Fan, Quan; Qiang, Rendeng; Engelhard, Mark H; Wang, Chong M; Lin, Yuehe; Zhong, Chuan-Jian

This paper reports findings of an investigation of the synthesis of monolayer-capped iron oxide and core (iron oxide)–shell (gold) nanocomposite and their assembly towards thin film materials. Pre-synthesized and size-defined iron oxide nanoparticles were used as seeding materials for the reduction of gold precursors, which was shown to be effective for coating the iron oxide cores with gold shells (Fe oxide@Au). The unique aspect of our synthesis is the formation of Fe oxide@Au core–shell nanoparticles with controllable surface properties. The novelty of our assembly strategy is the exploitation of the ligand-exchange reactivity at the gold shells for the thin film assembly of the core–shell nanoparticles. The core–shell nanocomposites and assemblies have been characterized using TEM, XRD, XPS, FTIR, TGA, and DCP-AES techniques. In addition to evidence from TEM detection of the change in particle size, UV-Vis observation of the change in the surface plasmon resonance band, and XRD detection of disappearance of the magnetite diffraction peaks after coating the gold shell, the formation of the core–shell morphology was further confirmed by DCP-AES composition analysis of Au and Fe in the molecularly-mediated thin film assembly of Fe oxide@Au particles. The interparticle ligand exchange–precipitation chemistry at the gold shell is to our knowledge the first example demonstrating the inter-shell reactivity for constructing thin films of Fe oxide@Au particles. The results have provided important insights into the design of interfacial reactivities via core–shell nanocomposites for magnetic, catalytic and biosensing applications.

• Research Organization: Pacific Northwest National Laboratory (PNNL), Richland, WA (US), Environmental Molecular Sciences Laboratory (EMSL)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC05-76RL01830
• OSTI ID: 15020659
• Report Number(s): PNNL-SA-45191; 2506; 6899; KP1302000
• Journal Information: Journal of Materials Chemistry, 15(18):1821-1832, Journal Name: Journal of Materials Chemistry, 15(18):1821-1832 Journal Issue: 18 Vol. 15
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
CHEMISTRY
COATINGS
DETECTION
DIFFRACTION
Environmental Molecular Sciences Laboratory
GOLD
ION EXCHANGE
IRON
IRON OXIDES
LIGANDS
MAGNETITE
MORPHOLOGY
Nanotechnology
nanoparticles
PARTICLE SIZE
PLASMONS
RESONANCE
SURFACE PROPERTIES
SYNTHESIS
THIN FILMS
X-RAY DIFFRACTION
X-RAY PHOTOELECTRON SPECTROSCOPY