Interfacial crystallization at the intersection of thermodynamic and geometry

Area of Science:

• Materials Science and Engineering
• Physical Chemistry
• Crystallography

Background:

• Interfacial crystallization is fundamental to numerous natural phenomena and technological processes, including semiconductor manufacturing and nanoparticle synthesis.
• Understanding the interplay between thermodynamics and geometry is key to controlling interfacial crystallization.
• Existing models like the Wulff and Winterbottom constructions provide frameworks for analyzing crystal shapes at interfaces.

Purpose of the Study:

• To survey the interfacial aspects of heterogeneous crystallization, focusing on thermodynamic and geometric influences.
• To introduce and discuss the concept of equivalent equilibrium contact angle (θeq) for isotropic crystals.
• To review the thermodynamic conditions favoring surface crystallization and its relation to wetting phenomena and practical applications.

Main Methods:

• Theoretical analysis of thermodynamic principles governing crystal growth at interfaces.
• Discussion of Wulff and Winterbottom constructions for predicting equilibrium crystal shapes.
• Review of experimental and theoretical studies on interfacial crystallization phenomena.

Main Results:

• The equivalent equilibrium contact angle (θeq) for isotropic crystals is independent of particle volume and external fields, unaffected by bulk energy contributions.
• The Winterbottom construction is applicable for predicting nanoparticle shapes on solid substrates.
• A thermodynamic condition for surface crystallization favoring over bulk crystallization is identified, coinciding with partial wetting conditions.

Conclusions:

• Interfacial crystallization is critically dependent on the balance of surface and interface energies, as described by geometric constructions.
• The concept of θeq simplifies the understanding of equilibrium crystal shapes at interfaces.
• Insights into interfacial crystallization are relevant for phenomena like the 'coffee-stain' effect, salt creeping, anti-icing surfaces, and epitaxial growth.