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A laminated thin-film composite (TFC) membrane system consisting of an ultrafiltration support, an ordered, nanoporous, polymerized lyotropic liquid crystal (LLC) intermediate layer, and an ultrathin, dense polydopamine top layer was developed for use as a “breathable” chemical-protective garment material. These membranes exhibit a high water vapor transport rate (ca. 500 g m–2 day–1) and excellent rejection of both CEES (a blister agent simulant) and DMMP (a nerve agent simulant) vapors under ambient conditions. The (water:CEES) and (water:DMMP) molar vapor selectivity values of this new composite membrane system were found to be 170 ± 40 and >3400, respectively, which exceed those of any previously reported LLC-based membrane system.

Anion exchange membranes (AEMs) play an essential role in artificial photosynthesis devices, which photoelectrochemically convert CO2 and water into useful products. AEMs allow the transport of charge carriers between electrodes while minimizing the transport of CO2 reduction products (e.g., ethanol). Fundamental transport studies in AEMs relevant to artificial photosynthesis are uncommon. Herein, we describe the preparation of an imidazoliumfunctionalized poly(phenylene oxide) membrane. Membrane transport properties were controlled by systematic variation of the degree of imidazolium functionalization, which induced changes in the membrane water volume fraction. Ethanol permeability and ionic conductivity increased with membrane water volume fraction. Consequently, membranes of relatively high ionic conductivity exhibited relatively high ethanol permeability, presenting a tradeoff in the transport properties desirable for artificial photosynthesis applications. This work seeks to enable optimization of AEMs for artificial photosynthesis through systematic study of membrane structure (water volume fraction) and its relevance to alcohol transport and electrolyte ion conductivity.