Displacement of Thiophene by Methanethiol Observed in Situ by Scanning Tunneling Microscopy and Quartz Crystal Oscillator Gravimetric Analysis on Au(111)
Autor: | John C. Hemminger, Mark H. Dishner, Peter Taborek, Frank J. Feher |
---|---|
Rok vydání: | 1998 |
Předmět: |
Chemistry
Analytical chemistry Surfaces and Interfaces Quartz crystal microbalance Condensed Matter Physics Isotropic etching law.invention chemistry.chemical_compound Chemisorption law Vacancy defect Monolayer Electrochemistry Thiophene General Materials Science Scanning tunneling microscope Spectroscopy Surface reconstruction |
Zdroj: | Langmuir. 14:6676-6680 |
ISSN: | 1520-5827 0743-7463 |
DOI: | 10.1021/la980274o |
Popis: | Quartz crystal microbalance and scanning tunneling microscopy experiments have been used to demonstrate that self-assembled monolayers of thiophene on gold can be quantitatively replaced by absorption of methanethiol from the gas phase. Adsorption of thiophene on the gold surface results in the relaxation of the clean gold surface reconstruction and the formation of vacancy islands or pits in the gold. Subsequent annealing of the monolayer can result in the complete removal of the vacancy islands. Methanethiol displacement of thiophene monolayers that have been previously annealed to remove vacancy island pits does not generate additional pits in the gold surface. Thus, ordered methanethiol monolayers which are free from vacancy island pits in the underlying gold surface can be formed by displacement of annealed thiophene monolayers. These results provide strong additional evidence that the formation of vacancy islands in the gold during the formation of alkanethiol SAMs is directly associated with relaxation of the clean surface reconstruction, rather than conventional chemical etching of the surface by alkanethiol. |
Databáze: | OpenAIRE |
Externí odkaz: |