Molecular interactions between organized, surface-confined monolayers and vapor-phase probe molecules. 6. In-situ FT-IR external reflectance spectroscopy of monolayer adsorption and reaction chemistry
| Autor: | Larry J. Kepley, Li Sun, Chuanjing Xu, Richard M. Crooks, Antonio J. Ricco |
|---|---|
| Rok vydání: | 1993 |
| Předmět: | |
| Zdroj: | Analytical Chemistry. 65:2102-2107 |
| ISSN: | 1520-6882 0003-2700 |
| Popis: | A new in-situ application of FTIR external reflectance spectroscopy (FTIR-ESR), which is useful for real-time evaluation of monolayer and multilayer adsorption and reaction chemistry at the vapor/solid interface at pressures near 1 atm, is described. The utility and versatility of the method is illustrated by two proof-of-concept experiments. The first experiment involves adsorption of H[sub 2]N(CH[sub 2])[sub 9]CH[sub 3] onto a naked Au substrate from the vapor phase. In-situ FTIR-ERS indicates that the amine forms a stable, ordered monolayer on the Au surface; that is, H[sub 2]N(CH[sub 2])[sub 9]CH[sub 3] self-assembles onto the Au surface from the vapor phase. The second experiment involves vapor-phase adsorption of a HS(C[sub 6]H[sub 5])OH monolayer onto a naked Au surface, followed by an in-situ coupling reaction with [CH[sub 3](CH[sub 2])[sub 7]](CH[sub 3])[sub 2]SiCl. Real-time FTIR-ERS characterization of the organic bilayer is consistent with previously reported ex-situ FTIR-ERS results; however, kinetic data can be abstracted from the new in-situ data. The rate constant for the surface silane coupling reaction is estimated to be 0.30 min[sup [minus]1]. 21 refs., 8 figs. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|