Functional nanoporous polymer membranes with expanded surface area can be applied in broad fields,
including separation, filtration, catalysis and energy applications. There are a number of established
fabrication methods to such membranes using neutral or weakly charged polymers. However, nanoporous
polymer membranes of high charge density remains challenging. Here we provide an easy access to
nanoporous polyelectrolyte membranes by using poly(ionic liquid)s.1
Poly(ionic liquid)s (PILs) are the polymerization products of ionic liquids (ILs), which combine properties
of polymers and ILs. We exploited these favorable properties to fabricate nanoporous PIL membranes via
electrostatic complexation of PILs with polyacids, as shown in Fig. 1.2 The as-obtained nanoporous
membrane features a gradient property profile along the membrane cross-section, triggered by the diffusive
penetration of ammonia from top to bottom into the PIL-polyacid blend film.
The combination of nanoconfinement and high ion density superimposed by structural gradient
differentiates the PIL membrane significantly from traditional porous polymer membranes. For example,
the gradient profile renders new functions far beyond filtration, e.g. the membrane can exhibit high
actuation speed in response to organic vapor. Such membranes may serve as environmental sensors to detect
chemicals.3,4 Our latest advance pushes forward their application scope to nanoporous carbon membranes
that have tremendous potential in electrochemical energy conversion/storage field.5-6
References
[1] Q. Zhao, M. Yin, A. P. Zhang, S. Prescher, M. Antonietti, and J. Yuan, J. Am. Chem. Soc. 135
(2013) 5549.
[2] Q. Zhao, J. W. C. Dunlop, X. Qiu, F. Huang, Z. Zhang, J. Heyda, J. Dzubiella, M. Antonietti, and J.
Yuan, Nat. Commun. 5 (2014) 4293.
[3] Z. Qiang, J. Heyda, J. Dzubiella, J. W. C. Dunlop, and J. Yuan, Adv. Mater. 27 (2015) 2913.
[4] J. Sun, W. Zhang, R. Guterman, H. Lin, Nat. Commun. 2018, accepted.
[5] H. Wang, Yuan, J., et al. Nat. Commun. 8 (2017) 13592.
[6] Wang, H.; Yuan, J., et al. Angew. Chem. Int. Ed. 56 (2017),7847