Article

The Chemistry of the Sulfur-Gold Interface: In Search of a Unified Model

Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas, Universidad Nacional de La Plata - CONICET, Argentina.
Accounts of Chemical Research (Impact Factor: 22.32). 03/2012; 45(8):1183-92. DOI: 10.1021/ar200260p
Source: PubMed

ABSTRACT

Over the last three decades, self-assembled molecular films on solid surfaces have attracted widespread interest as an intellectual and technological challenge to chemists, physicists, materials scientists, and biologists. A variety of technological applications of nanotechnology rely on the possibility of controlling topological, chemical, and functional features at the molecular level. Self-assembled monolayers (SAMs) composed of chemisorbed species represent fundamental building blocks for creating complex structures by a bottom-up approach. These materials take advantage of the flexibility of organic and supramolecular chemistry to generate synthetic surfaces with well-defined chemical and physical properties. These films already serve as structural or functional parts of sensors, biosensors, drug-delivery systems, molecular electronic devices, protecting capping for nanostructures, and coatings for corrosion protection and tribological applications.

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    • "The S 2p spectra obviously differ from those reported for gold sulfide materials [23–25,35], which exhibit a major line at about 162.5 eV and two weaker ones at about 163.2 eV and 161.5 eV. The latter spectra suggest substantial S–S bonding, alike to sulfur adsorbed onto metallic gold [26] [27], and it was proposed that the surface layer of gold sulfides decomposed yielding Au "
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    • "However, such agents might become poison for the Stöber silica doped/coated/supported gold nanoparticles especially when they are applied in the catalysis field that is another renowned field of gold. Take the thiol-contained agent for instance, the S component as the impurity of the agents can be strongly adsorbed onto gold nanoparticles [24], thus hinders the adsorption of reactants and even changes the sample structure [25]. Besides, the removal of these agents requires higher temperature [26] that is undesired for the gold nanoparticles in the catalysis field. "
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