Nanoscale chemical imaging of interfacial monolayers by tip-enhanced raman spectroscopy
| Autor: | Yao Zhang, Vivian Müller, Renato Zenobi, A. Dieter Schlüter, Feng Shao |
|---|---|
| Přispěvatelé: | China Scholarship Council, ETH Zurich |
| Rok vydání: | 2017 |
| Předmět: |
Chemical imaging
Chemistry Analytical chemistry Stacking General Medicine 02 engineering and technology General Chemistry 010402 general chemistry 021001 nanoscience & nanotechnology 01 natural sciences Catalysis 0104 chemical sciences symbols.namesake Chemical physics Monolayer Dispersion (optics) symbols Density functional theory 0210 nano-technology Raman spectroscopy Nanoscopic scale Image resolution |
| Zdroj: | Digital.CSIC. Repositorio Institucional del CSIC instname |
| Popis: | We report an investigation of interfacial fluorinated hydrocarbon (carboxylic-fantrip) monolayers by nanoscale imaging using tip-enhanced Raman spectroscopy (TERS) and density functional theory (DFT) calculations. By comparing TERS images of a sub-monolayer prepared by spin-coating and a π–π-stacked monolayer on Au(111) in which the molecular orientation is confined, specific Raman peaks shift and line widths narrow in the transferred LB monolayer. Based on DFT calculations that take into account dispersion corrections and surface selection rules, these specific effects are proposed to originate from π–π stacking and molecular orientation restriction. TERS shows the possibility to distinguish between a random and locked orientation with a spatial resolution of less than 10 nm. This work combines experimental TERS imaging with theoretical DFT calculations and opens up the possibility of studying molecular orientations and intermolecular interaction at the nanoscale and molecular level. We thank the ETH Zürich for financial support. F.S. thanks the Chinese Scholarship Council for a Ph.D. student fellowship. |
| Databáze: | OpenAIRE |
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