Tuning ice nucleation with counterions on polyelectrolyte brush surfaces

Z. He, W. J. Xie, Z. Liu, G. Liu, Z. Wang, Y. Q. Gao, J. Wang
2016 Science Advances  
Heterogeneous ice nucleation (HIN) on ionic surfaces is ubiquitous in a wide range of atmospheric aerosols and at biological interfaces. Despite its great importance in cirrus cloud formation and cryopreservation of cells, organs, and tissues, it remains unclear whether the ion-specific effect on ice nucleation exists. Benefiting from the fact that ions at the polyelectrolyte brush (PB)/water interface can be reversibly exchanged, we report the effect of ions on HIN on the PB surface, and we
more » ... cover that the distinct efficiency of ions in tuning HIN follows the Hofmeister series. Moreover, a large HIN temperature window of up to 7.8°C is demonstrated. By establishing a correlation between the fraction of ice-like water molecules and the kinetics of structural transformation from liquid-to icelike water molecules at the PB/water interface with different counterions, we show that our molecular dynamics simulation analysis is consistent with the experimental observation of the ion-specific effect on HIN.
doi:10.1126/sciadv.1600345 pmid:27386581 pmcid:PMC4928907 fatcat:ixzysqswp5enliykeyeukq5v34