Spatiotemporal catalytic dynamics within single nanocatalysts revealed by single-molecule microscopy

Area of Science:

• Nanotechnology
• Surface Chemistry
• Catalysis

Background:

• Understanding nanoparticle catalysis is crucial for developing efficient chemical processes.
• Previous studies often averaged catalytic behavior, masking dynamic single-particle phenomena.
• Single-molecule techniques offer unprecedented resolution for studying nanoparticle activity.

Purpose of the Study:

• To review advances in single-molecule microscopy for studying nanoparticle catalysis.
• To elucidate the spatiotemporal catalytic behaviors of individual metal nanoparticles.
• To correlate catalytic activity with nanoparticle structure and dynamics.

Main Methods:

• Single-molecule microscopy of fluorogenic reactions.
• Real-time single-turnover kinetics measurements.
• Single-molecule super-resolution catalysis imaging.

Main Results:

• Identified size-, catalysis-, and metal-dependent temporal activity fluctuations in nanoparticles.
• Related catalytic dynamics to quantifiable nanoparticle surface restructuring.
• Quantified catalytic activities at distinct surface sites (e.g., corners, edges, facets).
• Uncovered activity gradients on nanocrystal surfaces linked to surface site distribution.

Conclusions:

• Single-molecule microscopy provides detailed insights into nanoparticle catalytic heterogeneity.
• Nanoparticle surface restructuring and defect site distribution significantly influence catalytic activity.
• This approach can be extended to non-fluorescent catalytic systems.