Effects of changes in the interparticle separation induced by alkanethiols on the surface plasmon band and other properties of nanocrystalline gold films

Effects of changing the interparticle separation on the surface plasmon bands of ultrathin films of gold nanoparticles have been investigated by examining the interaction of alkanethiols of varying chain length on nanocrystalline gold films generated at the organic-aqueous interface. Adsorption of a...

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Veröffentlicht in:Langmuir : the ACS journal of surfaces and colloids. - 1992. - 24(2008), 6 vom: 18. März, Seite 2494-500
1. Verfasser: Agrawal, Ved Varun (VerfasserIn)
Weitere Verfasser: Varghese, Neenu, Kulkarni, G U, Rao, C N R
Format: Online-Aufsatz
Sprache:English
Veröffentlicht: 2008
Zugriff auf das übergeordnete Werk:Langmuir : the ACS journal of surfaces and colloids
Schlagworte:Journal Article Research Support, Non-U.S. Gov't Alkanes Membranes, Artificial Sulfhydryl Compounds Water 059QF0KO0R Gold 7440-57-5
Beschreibung
Zusammenfassung:Effects of changing the interparticle separation on the surface plasmon bands of ultrathin films of gold nanoparticles have been investigated by examining the interaction of alkanethiols of varying chain length on nanocrystalline gold films generated at the organic-aqueous interface. Adsorption of alkanethiols causes blue-shifts of the surface plasmon adsorption band, the magnitude of the shift being proportional to the chain length. The disordered nanocrystals thus created (lambdamax, 530 m) are in equilibrium with the ordered nanocrystals in the film (lambdamax, 700 m) as indicated by an isosbestic point around 600 nm. Long chain thiols disintegrate or disorder the gold films more effectively, as demonstrated by the increased population of the thiol-capped gold nanocrystals in solution. The rate of interaction of the thiols with the film decreases with the decreasing chain length. The effect of an alkanethiol on the spectrum of the gold film is specific, in that the effects with long and short chains are reversible. The changes in the plasmon band of gold due to interparticle separation can be satisfactorily modeled on the basis of the Maxwell-Garnett formalism. Spectroscopic studies, augmented by calorimetric measurements, suggest that the interaction of alkanethiols involves two steps, the first step being the exothermic gold film-thiol interaction and the second step includes the endothermic disordering process followed by further thiol capping of isolated gold particles
Beschreibung:Date Completed 14.05.2008
Date Revised 21.11.2013
published: Print-Electronic
Citation Status MEDLINE
ISSN:1520-5827
DOI:10.1021/la703237m