Our study titled “Mobility of Condensed Counterions in Ion-Exchange Membranes: Application of Screening Length Scaling Relationship in Highly Charged Environments” has been published in Environmental Science & Technology.
Ion-exchange membranes (IEMs) are widely used in water, energy, and environmental applications. However, there are presently no fundamentally rigorous transport models to accurately simulate the permeation of counterions, the main charge carriers in IEMs. In this study, we introduced a theoretical framework to, for the first time, describe the mobility of condensed counterions and enable the improved prediction of IEM ionic conductivity. This is achieved by the novel use of a scaling relationship for screening lengths within the highly charged IEM matrices to overcome the obstacle of traditional electrolyte chemistry theories breaking down at very high ionic strength environments. Because the transport framework is based on first principles, findings of the study can provide fundamental insights into the underlying phenomena governing ion transport in IEMs and inform the rational development of more selective membranes.
