Charge separation at evaporation and vapor growth of ice and water

Abstract

A mathematical model of the interface charging at evaporation and growth of ice and water phases from vapor is proposed. This model takes into account the competition between the two mechanisms of charge separation, one of which is based on protons and the other involves orientational defects. The first mechanism leads to the accumulation of a positive charge by ice and water during evaporation, while the second one provides negative charge accumulation. The protonic mechanism dominates at low velocities of the evaporation front with respect to the condensed phase material (lower than 10−11–10−9 m/s). At high rates, the mechanism based on orientational defects is dominant. When vapor is condensed, and, correspondingly, the ice and water phases grow, the charge polarity is opposite to the polarity in the case of evaporation. The proposed model adequately describes the experimentally observed interface electric current and the signs of phase charges during evaporation and condensation.