Heat Engine Drives Transport of an FeII4L4 Cage and Cargo. Issue 19 (1st April 2020)

• Record Type: Journal Article
• Authors: Nguyen, Bao‐Nguyen T.; Grommet, Angela B.; Tron, Arnaud; Georges, Maureen C. A.; Nitschke, Jonathan R.
• Is Part Of: Advanced materials. Volume 32:Issue 19(2020)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2020-04-01
• Subjects: metal organic cages -- molecular cargo transport -- phase transfer -- supramolecular chemistry -- thermally responsive materials; Materials -- Periodicals; Chemical vapor deposition -- Periodicals; 620.11
• DOI: 10.1002/adma.201907241
• Languages: English
• ISSNs: 0935-9648

Abstract

Abstract: The directed motion of species against a chemical potential gradient is a fundamental feature of living systems, underpinning processes that range from transport through cell membranes to neurotransmission. The development of artificial active cargo transport could enable new modes of chemical purification and pumping. Here, a heat engine is described that drives chemical cargo between liquid phases to generate a concentration gradient. The heat engine, composed of a functionalized Fe II 4 L4 coordination cage, is grafted with oligoethylene glycol imidazolium chains. These chains undergo a conformational change upon heating, causing the cage and its cargo to reversibly transfer between aqueous and organic phases. Furthermore, sectional heating and cooling allow for the cage to traverse multiple phase boundaries, allowing for longer‐distance transport than would be possible using a single pair of phases. Abstract : A heat engine composed of a coordination cage, Fe II 4 L4, decorated with thermoresponsive chains, is constructed. Upon heating and cooling, the chains expand and contract, thereby modulating the solubility preferences of the cage. Through application of a thermal gradient, the cage reversibly transfers between water and ethyl acetate, pumping its encapsulated molecular cargo along the length of a tube and back again.