Surface Chemistry of 4-Mercaptobenzoic Acid Self-Assembled on Ag(111) and Ag Nanoparticles.
The adsorption of 4-mercaptobenzoic acid (MBA) on Ag(111) and Ag nanoparticles (AgNPs) has been studied by X-ray photoelectron spectroscopy (XPS), electrochemical techniques, high-resolution transmission electron microscopy (HRTEM), and density functional theory (DFT) calculations. Results show that...
| Autores: | , , , , , , |
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| Tipo de recurso: | artículo |
| Estado: | Versión publicada |
| Fecha de publicación: | 2013 |
| País: | Argentina |
| Institución: | Consejo Nacional de Investigaciones Científicas y Técnicas |
| Repositorio: | CONICET Digital (CONICET) |
| Idioma: | inglés |
| OAI Identifier: | oai:ri.conicet.gov.ar:11336/1275 |
| Acceso en línea: | http://hdl.handle.net/11336/1275 |
| Access Level: | acceso abierto |
| Palabra clave: | 4-Mercaptobenzoic Acid (Mba) Ag(111) And Ag Nanoparticles (Agnps) Xps, Hrtem,Dft,Electrochemical Techniques https://purl.org/becyt/ford/1.4 https://purl.org/becyt/ford/1 |
| Sumario: | The adsorption of 4-mercaptobenzoic acid (MBA) on Ag(111) and Ag nanoparticles (AgNPs) has been studied by X-ray photoelectron spectroscopy (XPS), electrochemical techniques, high-resolution transmission electron microscopy (HRTEM), and density functional theory (DFT) calculations. Results show that MBA molecules adsorb intact on the Ag (111) surface via a thiolate bond, arranged in a (√3 × 4) lattice with coverage θ = 0.25. The phase diagram built using DFT data shows that this lattice is more stable than the dense (√7 × √7)R19.1 MBA lattices on reconstructed Ag(111) surfaces. No significant amounts of sulfide were found neither on the Ag(111) surfaces nor on MBA-protected AgNPs, suggesting that the Ag core@Ag-sulfide shell structure where thiolates could be grafted cannot be applied to the MBA-protected AgNPs. Slow degradation of the MBA protective layer in ambient conditions on the AgNPs results in disulfide formation and AgNP sintering. |
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