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Merging Ion Concentration Polarization between Juxtaposed Ion Exchange Membranes to Block the Propagation of the Polarization Zone
Published on: February 23, 2017
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Morphology-Controlled Ion Transport in Mixed-Orientation Polymers.
Boya Zhang1, Lanyi Xiang1, Chaoyi Yan1
1School of Chemical Sciences, University of Chinese Academy of Sciences, Beijing 101408, People's Republic of China.
ACS Applied Materials & Interfaces
|June 11, 2024
Summary
A new mixed-orientation strategy in conjugated polymers enables efficient ion transport for organic electronics while minimizing leakage. This breakthrough advances iontronics and paves the way for multifunctional ion pump devices.
Area of Science:
- Iontronics
- Organic Electronics
- Materials Science
Background:
- Bridging external organic electronics with biosystems requires precisely controlled ion transport.
- Current limitations in (semi)crystalline films involve a trade-off between ion electromigration and diffusion leakage.
Purpose of the Study:
- To develop a strategy for simultaneous high ion electromigration efficiency and low leakage in iontronic devices.
- To engineer polymer composites with mixed orientations for switchable ion-transport behavior.
Main Methods:
- Blending conjugated polymers to create mixed orientations.
- Investigating ion permeability and leakage in edge-on versus face-on aggregation.
- Engineering mixed orientations to optimize ion transport.
Main Results:
- Edge-on aggregation showed higher ion permeability but also increased leakage compared to face-on.
- The engineered mixed-orientation polymer composite achieved high electromigration efficiency (>10^15 ions/mL/min).
- Negligible idle leakage was observed in the optimized composite.
Conclusions:
- A mixed-orientation strategy effectively balances ion electromigration and leakage in iontronic devices.
- This approach enables switchable ion-transport behavior for advanced applications.
- The proof of concept was validated in a skin-conformable organic electronic ion pump (OEIP) for drug delivery.
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