Tracking surface charge dynamics on single nanoparticles.

Area of Science:

• Physics and Chemistry
• Materials Science
• Nanotechnology

Background:

• Surface charges are critical for nanomaterial catalytic properties.
• Tracking nanoscale charge dynamics is difficult due to scale limitations.

Purpose of the Study:

• To demonstrate time-resolved access to nanoscale charge dynamics on dielectric nanoparticles.
• To visualize spatiotemporal evolution of charge density on individual SiO2 nanoparticles.

Main Methods:

• Utilized reaction nanoscopy for time-resolved measurements.
• Employed femtosecond-nanometer resolution for four-dimensional visualization.
• Conducted quantum dynamical and semi-classical simulations.

Main Results:

• Observed biexponential redistribution of initially localized surface charges over time.
• Revealed the influence of surface charges on surface molecular bonding.
• Uncovered the roles of diffusion and charge loss in charge redistribution.

Conclusions:

• Understanding nanoscale surface charge dynamics is key to advancing renewable energy and healthcare.
• Single-nanoparticle charge dynamics influence chemical bonding.
• This work provides a new method for studying charge dynamics at the nanoscale.