What Makes a Good Descriptor for Heterogeneous Ice Nucleation on OH-Patterned Surfaces

TL;DR

This study investigates the factors influencing heterogeneous ice nucleation on hydroxylated surfaces, revealing that OH density and interaction strength are key descriptors, which can guide the design of effective ice nucleators.

Contribution

The paper identifies OH density and substrate-water interaction strength as crucial descriptors for ice nucleation ability, challenging previous assumptions about symmetry and similarity to ice.

Findings

OH density correlates with nucleation efficiency

Interaction strength influences ice formation

Symmetry and ice similarity are not reliable predictors

Abstract

Freezing of water is arguably one of the most common phase transitions on Earth and almost always happens heterogeneously. Despite its importance, we lack a fundamental understanding of what makes substrates efficient ice nucleators. Here we address this by computing the ice nucleation (IN) ability of numerous model hydroxylated substrates with diverse surface hydroxyl (OH) group arrangements. Overall, for the substrates considered, we find that neither the symmetry of the OH patterns nor the similarity between a substrate and ice correlate well with the IN ability. Instead, we find that the OH density and the substrate-water interaction strength are useful descriptors of a material's IN ability. This insight allows the rationalization of ice nucleation ability across a wide range of materials, and can aid the search and design of novel potent ice nucleators in the future.