Shape selection in diffusive growth of colloids and nanoparticles

Area of Science:

• Materials Science
• Chemical Engineering
• Computational Physics

Background:

• Particle synthesis often yields uniform colloids and nanoparticles.
• Understanding the fundamental mechanisms driving shape uniformity is crucial for materials design.

Purpose of the Study:

• To investigate the numerical model of diffusive growth for fine particles with various crystal lattices.
• To explain the emergence of uniform particle shapes in colloidal and nanoparticle synthesis.

Main Methods:

• Developed a 3D numerical model simulating diffusive growth of crystalline particles.
• Incorporated on-surface dynamics including monomer detachment and motion to vacant crystal sites.
• Focused on defect-free core growth imposed by specific dynamic rules.

Main Results:

• Demonstrated that defect-free core growth can lead to uniform particle shapes.
• Showed that specific shapes emerge following crystal symmetry, driven by nonequilibrium growth.
• Identified control over particle shape through kinetic rates and monomer concentration.

Conclusions:

• The model provides a potential explanation for experimentally observed shape uniformity in nanoparticle synthesis.
• Highlights the role of nonequilibrium dynamics in forming well-defined, uniform particle shapes.
• Suggests tunable control over particle morphology by adjusting growth conditions.