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Abstract MXenes are among the fastest‐growing families of 2D materials, promising for high‐rate, high‐energy energy storage applications due to their high electronic and ionic conductivity, large surface area, and reversible surface redox ability. The Ti3C2TxMXene shows a capacitive charge storage mechanism in diluted aqueous LiCl electrolyte while achieving abnormal redox‐like features in the water‐in‐salt LiCl electrolyte. Herein, variousoperandotechniques are used to investigate changes in resistance, mass, and electrode thickness of Ti3C2Txduring cycling in salt‐in‐water and water‐in‐salt LiCl electrolytes. Significant resistance variations due to interlayer space changes are recorded in the water‐in‐salt LiCl electrolyte. In both electrolytes, conductivity variations attributed to charge carrier density changes or varied inter‐sheet electron hopping barriers are detected in the capacitive areas, where no thickness variations are observed. Overall, combining thoseoperandotechniques enhances the understanding of charge storage mechanisms and facilitates the development of MXene‐based energy storage devices.
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This content will become publicly available on August 13, 2026
Tuning Water Transport through Nanochannels of Robust Cation‐Intercalated Ti 3 C 2 T x MXene Membranes
Ti3C2TxMXene membranes have attracted considerable interest due to their exceptional water transport properties, yet the role of cation intercalation on governing transport remains poorly understood. In this experimental and theoretical study, it shows how intercalation with K+, Na+, Li+, Ca2+, and Mg2+modulates both the nanochannel architecture and water flux of Ti3C2Txmembranes. Unlike in graphene oxide analogs, cations with larger hydration diameters in Ti3C2Txexpand the interlayer spacing, widening flow channels, enhancing slip length of these nanochannels, and boosting water flux from 31.45 to 61.86 L m−2 h−1. To overcome intrinsically poor adhesion of Ti3C2Txto polymeric supports, this study incorporates a thin polyvinyl‐alcohol interlayer, which substantially enhances mechanical robustness and structural integrity. Together, these findings elucidate how cation hydration controls water transport and offer a flexible strategy for tailoring MXene membrane performance.
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- Award ID(s):
- 2134607
- PAR ID:
- 10633002
- Publisher / Repository:
- Chemistry Europe
- Date Published:
- Journal Name:
- ChemSusChem
- ISSN:
- 1864-5631
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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