Abstract Shape‐persistent, conductive ionogels where both mechanical strength and ionic conductivity are enhanced are developed using multiphase materials composed of cellulose nanocrystals and hyperbranched polymeric ionic liquids (PILs) as a mechanically strong supporting network matrix for ionic liquids with an interrupted ion‐conducting pathway. The integration of needlelike nanocrystals and PIL promotes the formation of multiple hydrogen bonding and electrostatic ionic interaction capacitance, resulting in the formation of interconnected networks capable of confining a high amount of ionic liquid (≈95 wt%) without losing its self‐sustained shape. The resulting nanoporous and robust ionogels possess outstanding mechanical strength with a high compressive elastic modulus (≈5.6 MPa), comparable to that of tough, rubbery materials. Surprisingly, these rigid materials preserve the high ionic conductivity of original ionic liquids (≈7.8 mS cm−1), which are distributed within and supported by the nanocrystal network‐like rigid frame. On the one hand, such stable materials possess superior ionic conductivities in comparison to traditional solid electrolytes; on the other hand, the high compression resistance and shape‐persistence allow for easy handling in comparison to traditional fluidic electrolytes. The synergistic enhancement in ion transport and solid‐like mechanical properties afforded by these ionogel materials make them intriguing candidates for sustainable electrodeless energy storage and harvesting matrices.
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Ion transport in polymeric ionic liquids: recent developments and open questions
Polymeric ionic liquids (PILs) are an emerging class of materials that combine the attractive properties of ionic liquids with the sequence complexity and mechanical characteristics of macromolecules. While significant advances have occurred in the context of synthesis and characterization of such materials, comparatively less understanding exists on the mechanisms underlying ion transport in such materials. In this perspective article, the status of understanding in related systems of salt-doped polymer electrolytes, (non-ionic-liquid-based) single-ion polymer conductors and room temperature ionic liquids is briefly reviewed. Subsequently, some recent developments in the context of PILs are discussed to identify some open questions confronting the issue of ion transport in such materials.
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- PAR ID:
- 10096918
- Date Published:
- Journal Name:
- Molecular Systems Design & Engineering
- Volume:
- 4
- Issue:
- 2
- ISSN:
- 2058-9689
- Page Range / eLocation ID:
- 280 to 293
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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