Molecular Dynamics Simulation of the Enhanced Evaporation Characteristics of Pure Water and Ion Solutions by the Electric Field

In this study, the evaporation of pure water and NaCl solution films under different electric fields was investigated using molecular dynamics, and the intrinsic mechanism of enhanced evaporation by electric fields was analyzed from the perspectives of forces and thermodynamics. The simulations showed that, apart from a slight inhibitory effect of a direct current electric field on the evaporation efficiency of pure water, square wave electric fields promoted the evaporation of both pure water and NaCl solution, as well as direct current electric fields on NaCl solution, with the effect increasing with the strength and frequency of the field. For example, under a 200 GHz square wave electric field, the evaporation rates of the pure water and NaCl solution films were 8.33 and 2.65 times higher than under the direct current electric field, respectively; under horizontal electric fields of 0.1 V/nm and 0.3 V/nm, the evaporation rates of the NaCl solution film were 1.13 and 1.66 times higher than natural evaporation, respectively. The rate of evaporation efficiency is reflected in the change of molecular kinetic energy. The reasons for these phenomena are closely related to microscopic parameters and properties such as intermolecular forces, the number of hydrogen bonds, and the coordination number.The application of different electric fields affects the microscopic properties between molecules, leading to changes in the evaporation rate.