This study aims at developing membranes with unprecedented atomically precise separation accuracy and efficiency through a bottom-up approach, which are radically different from current polymeric membranes. We construct the ultrathin membranes by assembling designed, chemically synthesized channel molecules into two-dimensional dense arrays. The ultimately thin barriers are envisioned to offer an exceptional permeability. The large rigid channel structures with well-defined shapes are assembled from unique “Molecular Lego” building blocks. These stereochemically pure and highly functionable building blocks (bis-amino acids) are coupled to each other through pairs of amide bonds to create spiro-ladder oligomers or “spiroligomers” with programmed shapes like building with Legos. We utilize microwave peptide synthesizer to assemble spiroligomers into channel molecules on solid support in a sequence-controlled way. With this methodology, we have successfully synthesized rectangular and triangular macrocycles exhibiting uniform intrinsic pore sizes. The fabrication of atomically precise membranes (APMs) is enabled by two techniques: 1) Interfacial polymerization: cross-linking amine-functionalized macrocycles with trimesoyl chloride on support membrane surface in a manner similar to preparing polyamide thin film composite membranes; 2) Langmuir monolayer: self-assembling surfactant-like amphiphilic macrocycles into monolayers in the Langmuir trough and cross-linking them in-situ to form single-molecule thick stand-alone films followed by transferring to support membranes. Filtration tests are ongoing to demonstrate the precise separation capability of APMs.

Atomically precise membranes from molecular Legos

Macromolecular Chemistry: The Second Century

[Author Benefits](https://scimeetings.acs.org/?utm_source=pubs_content_marketing&utm_medium=website&utm_campaign=0320_MCF_NPI_Launch_Spring_Homepage&ref=pubs_content_marketing)

[How to use SciMeetings](https://storage.googleapis.com/dl.morressier.com/acs/SciMeetings-ACSSpring2020-HowToGuide_M3020-Final.pdf)

[Frequently Asked Questions](https://storage.googleapis.com/dl.morressier.com/acs/SciMtng_ACSNMSp2020_FAQ_M3120_Final.pdf)

ACS Spring 2020 National Meeting & Expo

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.