Two-dimensional (2D) ionogel membranes have emerged as a promising class of materials for broad applications in flexible electronics, smart robotics and artificial intelligence. However, the rapid, reliable and reproducible fabrication of ionogel membranes remains challenging due to difficult-to-control molecular behaviour. To overcome this challenge, we propose a ‘dip and peel’ strategy to exfoliate 2D ionogel membranes from a biomacromolecular gelatum (for example, a cellulose ionogel colloid) by controlling the solvent-induced supramolecular self-assembly. This strategy enables the simple and rapid fabrication of ionogel membranes with tunable shapes, controllable thicknesses, high ionic conductivity up to 14.1 mS cm−1, good stretchability exceeding 130% and excellent tandem duplication over 700 times. We further extend this strategy to fabricate different ionogel membranes from various biomacromolecules, including silk fibroin, chitosan and guar gum. Our results shed light on exploration of fundamental macromolecular interactions and provide an effective approach to prepare 2D biomacromolecular ionogel membranes with advanced functionalities.
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H.Y. and D.Z. acknowledge support by the National Science Fund for Distinguished Young Scholars of China (grant number 31925028) and the National Natural Science Foundation of China (grant number 32171720). G.Y. acknowledges support from the Welch Foundation F-1861, a Norman Hackerman Award in Chemical Research and a Camille Dreyfus Teacher-Scholar Award.
The authors declare no competing interests.
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Nature Synthesis thanks Jian Hu, Ho Seok Park and the other, anonymous, reviewer(s) for their contribution to the peer review of this work. Primary Handling Editor: Peter Seavill, in collaboration with the Nature Synthesis team.
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Supplementary Notes 1 and 2, Figs. 1–20 and Tables 1–5.
Solvent-induced exfoliation of P-membrane within 1 s.
A glass-rod-assisted transfer method to obtain a flat P-membrane.
Layer-by-layer peeling of the P-membranes.
Fabrication of a large-area P-membrane.
Inkjet printing the P-membrane-based flexible circuit chip.
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Zhu, Y., Guo, Y., Cao, K. et al. A general strategy for synthesizing biomacromolecular ionogel membranes via solvent-induced self-assembly. Nat. Synth 2, 864–872 (2023). https://doi.org/10.1038/s44160-023-00315-5