Abstract
While polymer membranes are used to remove salts from environmental and industrial electrolytes, it remains a significant challenge to engineer them to isolate a single dissolved species from complex mixtures, which is important for lithium mining, battery and magnet recycling, and microelectronics. Underpinning this challenge has been a lack of understanding of rate-limiting mechanisms in selective ion transport. Here, we show that hydrated ions exhibit higher free energies of activation when crossing solution-membrane interfaces (i.e., partitioning) than when diffusing through polymers, which challenges historical assumptions embedded in widely used models of membrane performance. We further articulate a framework benchmarked with quantitative capabilities for predicting how functionality within polymer membranes or at their surfaces affects selectivity toward individual dissolved species.
Original language | English (US) |
---|---|
Pages (from-to) | 2161-2183 |
Number of pages | 23 |
Journal | Matter |
Volume | 7 |
Issue number | 6 |
DOIs | |
State | Published - Jun 5 2024 |
Externally published | Yes |
All Science Journal Classification (ASJC) codes
- General Materials Science
Keywords
- MAP 3: Understanding
- desalination
- electrodialysis
- ion transport
- lithium
- membrane
- membrane selectivity
- polymers of intrinsic microporosity
- separation
- transition state theory