Visualizing On-Surface Decomposition Chemistry at the Nanoscale Using Tip-Enhanced Raman Spectroscopy

Area of Science:

• Surface Chemistry
• Nanotechnology
• Spectroscopy

Background:

• Understanding molecular decomposition at solid-liquid interfaces is crucial but challenging for conventional methods.
• Existing analytical tools lack the necessary chemical sensitivity and specificity at the nanoscale.

Purpose of the Study:

• To demonstrate high-resolution hyperspectral tip-enhanced Raman spectroscopy (TERS) imaging as a powerful tool for on-surface decomposition chemistry.
• To visualize the decomposition of a pyridine-4-thiol self-assembled monolayer on Au(111) surfaces.

Main Methods:

• Utilized hyperspectral tip-enhanced Raman spectroscopy (TERS) imaging.
• Applied density functional theory (DFT) simulations for species identification.

Main Results:

• Successfully visualized the on-surface decomposition process of pyridine-4-thiol.
• Detected reactive intermediates with 5 nm spatial resolution.
• Identified a key species as a disulfide reaction intermediate using TERS and DFT.

Conclusions:

• Hyperspectral TERS imaging is effective for studying nanoscale decomposition chemistry at solid-liquid interfaces.
• This method enables quantitative analysis of on-surface decomposition dynamics.
• Opens new avenues for chemical imaging of interfacial processes.