On 14 February 2025, researchers from the UNSAT Lab at Hunan University published a study titled “Water Nanofilms Facilitate Ice Crystal Growth across Droplets” in Physical Review Letters (PRL).

The study revealed a mechanism by which nanometer-thick water films can transmit freezing between separate supercooled droplets. Using high-speed imaging, the researchers showed that a connected water nanofilm thicker than a critical value of approximately 4.5 nm can facilitate the propagation of a freezing front from one droplet to its neighbors. The propagation rate through the nanofilm was approximately 40% of the recalescence-front growth rate within a droplet, with both processes described by kinetic crystal growth theory.

Water-nanofilm-mediated freezing propagation across droplets

The College of Civil Engineering at Hunan University was the primary institution for the work. Shaojie Hu was the first author and Prof. Chao Zhang was the first corresponding author. The study was coauthored by Ningning Zhao, Fuxiang Li, Renpeng Chen, and Dani Or, and was supported by the National Natural Science Foundation of China.

Physical Review Letters webpage for the published article

Paper: Physical Review Letters

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