Dynamic imaging reveals subnanometer gap distance controls electron transfer processes at plasmonic nanointerfaces.

Area of Science:

• Surface science
• Nanotechnology
• Electrochemistry

Background:

• Electron transfer at nanoscale gaps is vital for catalysis and nanophotonics.
• Experimentally visualizing these dynamics alongside gap evolution is challenging.
• Subnanometer resolution is needed to understand interfacial processes.

Purpose of the Study:

• To dynamically probe electron transfer at nanomaterial-electrode interfaces in real time.
• To correlate optical signatures with nanogap coupling and electron transfer.
• To establish a direct experimental framework for nanoscale electron transfer studies.

Main Methods:

• Utilized plasmonic scattering interferometric microscopy (PSIM).
• Employed nanoelectrochemical modulation for real-time probing.
• Combined experimental techniques with simulations for validation.

Main Results:

• Achieved subnanometer resolution in probing electron transfer dynamics.
• Correlated optical signatures with the nanogap coupling regime.
• Identified gap distance as the primary determinant of heterogeneous electron transfer.

Conclusions:

• Gap distance is the key factor governing heterogeneous electron transfer.
• Developed a framework for optical frequency probing of nanoscale electron transfer.
• Provides insights for designing electrocatalytic interfaces and nano-sensing platforms.