Chemically Tailorable Dissolution Pathways of Individual Cu₃As Nanocrystals.

Area of Science:

• Materials Science
• Nanotechnology
• Physical Chemistry

Background:

• Nanocrystal (NC) properties depend on size, shape, and composition.
• Controlling NC shape is key for designing advanced materials and understanding reaction kinetics.
• Liquid cell transmission electron microscopy (LCTEM) offers high-resolution, real-time observation of NC dynamics.

Purpose of the Study:

• To analyze single-particle etching trajectories of copper arsenide (Cu3As) nanocubes.
• To investigate how chemical environment manipulation influences NC shape transformations.
• To reveal mechanisms of kinetically controlled dissolution in binary semiconductors.

Main Methods:

• Utilized liquid cell transmission electron microscopy (LCTEM) for in-situ observation.
• Studied well-faceted copper arsenide (Cu3As) nanocubes.
• Manipulated the chemical environment by adjusting pH, coordination, concentration, and oxidative species.

Main Results:

• Identified distinct, kinetically controlled dissolution trajectories of Cu3As nanocubes.
• Demonstrated that nanoscale shape transformations can be directed by altering cationic and anionic reactivity.
• Observed shape changes within a nonequilibrium radiolysis liquid environment.

Conclusions:

• The chemical environment is a critical factor in controlling nanoscale shape transformations of binary semiconductors.
• LCTEM provides powerful insights into the fundamental kinetics of NC etching and dissolution.
• Precise control over NC shape is achievable through targeted chemical modulation.