Impact of surface nanostructure on ice nucleation

Area of Science:

• Materials Science
• Physical Chemistry
• Surface Science

Background:

• Ice nucleation on surfaces is crucial for many applications.
• Surface lattice parameters typically influence nucleation, but are difficult to tune.
• Nanoscale surface features offer potential for tunable ice nucleation control.

Purpose of the Study:

• To investigate the effect of nanoscale surface roughness on water nucleation.
• To determine if tunable surface structures can promote or inhibit ice nucleation.
• To explore the relationship between surface characteristic length and ice crystal structure.

Main Methods:

• Molecular dynamics simulations were employed to construct surfaces with periodic grooves.
• Water cylinders were simulated freezing under constant undercooling.
• The mean first-passage time method was used to calculate nucleation rates.

Main Results:

• Water nucleation is sensitive to the width of nanoscale surface grooves.
• Matching groove width to ice crystal structure significantly promotes nucleation.
• Mismatched groove widths reduce nucleation rates, even below smooth surfaces.
• Carefully designed surfaces can exhibit anti-icing properties by avoiding geometric matches.

Conclusions:

• Nanoscale surface topography, specifically groove width, is a key factor in controlling ice nucleation.
• Tailoring surface characteristic lengths offers a pathway to engineer ice nucleation promotion or inhibition.
• This research provides insights for designing advanced anti-icing surfaces.