Surface plasmon resonance method for probing interactions in nanostructures: CdS nanoparticles linked to Au and Ag substrates by self-assembled hexanedithiol and aminoethanethiol monolayers

Journal Article · Wed Aug 15 04:00:00 EDT 2001 · Journal of Applied Physics

DOI:https://doi.org/10.1063/1.1381546· OSTI ID:40230567

Hutter, E; Fendler, J H; Roy, D

Self-assembled hexanedithiol (HDT) and aminoethanethiol (AET) monolayers (SAMs), {approx}0.4--0.8 nm in thickness, are used to link {approx}5 nm diam CdS nanoparticles covalently and electrostatically onto Au and Ag substrates. The resulting nanostructures are probed with scanning electron microscopy (SEM) and surface plasmon resonance (SPR) measurements. The CdS nanoparticle--SAM--substrate interactions manifesting themselves in the dielectric functions of the multilayered systems, are detected in the SPR data, and are discussed in terms of a phenomenological six-layer model. The SPR response of the Ag substrate is more sensitive to neighboring interactions than the Au substrate. The SEM images show that the CdS, connected either by HDT or AET onto Ag substrates, forms crystalline structures. The interactions responsible for this crystallization are absent in samples employing Au substrates, in which case only {approx}5 nm diam CdS nanoparticles are detected by SEM. The experimental results of the present article, analyzed in detail using Fresnel and Maxwell equations, demonstrate how the SPR technique can be used to characterize layered nanostructured materials. {copyright} 2001 American Institute of Physics.

• Sponsoring Organization: (US)
• OSTI ID: 40230567
• Journal Information: Journal of Applied Physics, Journal Name: Journal of Applied Physics Journal Issue: 4 Vol. 90; ISSN 0021-8979
• Publisher: The American Physical Society
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
CRYSTALLIZATION
DIELECTRIC MATERIALS
MAXWELL EQUATIONS
MEA
PHYSICS
PLASMONS
RESONANCE
SCANNING ELECTRON MICROSCOPY
SUBSTRATES
THICKNESS