Visualizing the distribution of black carbon's electron storage capacity using silver

Area of Science:

• Environmental Chemistry
• Materials Science
• Microscopy

Background:

• Electron storage capacity (ESC) in black carbon (BC) is vital for environmental processes like contaminant fate and remediation.
• Understanding the spatial distribution of ESC on and within BC is critical for assessing bioaccessibility and reaction kinetics.

Purpose of the Study:

• To develop and validate a novel method for visualizing the distribution of electron storage capacity (ESC) in black carbon (BC).
• To investigate the locations and spatial distribution of ESC on and within BC particles.

Main Methods:

• Combined chemical reduction, silver ion (Ag+) tagging, and electron microscopy (EM).
• Silver nanoparticles (nAg) formed by reduced ESC were imaged using EM to map ESC distribution.
• Utilized multiple EM techniques for detailed visualization.

Main Results:

• Successfully visualized and confirmed significant ESC on both the surface and interior of BC particles.
• Demonstrated the spatial distribution of ESC within the BC matrix.
• Developed a novel method for incorporating silver or other redox-sensitive elements into carbon materials.

Conclusions:

• The developed method provides a new tool for probing and assessing ESC distribution in BC.
• Visual confirmation of internal ESC highlights its importance in BC's environmental functions.
• This technique advances the study of BC-mediated redox transformations.