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  1. Selective electrochemical separations can enable the recycling of valuable homogeneous catalysts for key industrial reactions. 
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  2. Abstract

    Synthetic chiral platforms can be a powerful platform for enantioselective interactions, especially when coupled with redox‐mediated electrochemical processes. While metallopolymers are versatile platforms for molecularly selective binding, their application for chiral applications is limited. In particular, the recognition and separation of biologically relevant chiral molecules can be key for biomanufacturing and diagnostics. Here, the design of chiral redox‐polymers enables electrochemically‐controlled enantioselective interactions, and supramolecular chirality is leveraged for enhancing recognition towards target enantiomers. Chiral redox‐metallopolymers are synthesized based on Ugi's amine‐inspired chiral monomers, and their enantioselective recognition toward ionic enantiomers such as tryptophan and naproxen is demonstrated, with higher enanhcement provided by the chiral redox‐polymer over the single‐site, chiral building bloack itelf. 2D nuclear magnetic resonance spectroscopy and solid‐state circular dichroism support the emergence of supramolecular chirality resulting from the intramolecular interaction between the ferrocene and the alkyl group in the backbone. The half potential shift of the redox‐polymers behaves linearly from 0% to 100%eel‐tryptophan to enable enantiomer quantification. Investigation on solvent polarity and pH effect reveal that the enantioselective mechanism is attributed to the subtle balance between hydrogen bonding and π–π interaction. This study highlights the potential of chiral redox‐metallopolymers as platforms for electrochemically‐modulated enantioselective interactions towards a range of amino acids and pharmaceutical carboxylates.

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  3. Abstract

    Electro‐responsive functional materials can play a critical role in selective metal recovery and recycling due to the need for molecular differentiation between transition metals in complex mixtures. Redox‐active metallopolymers are a promising platform for electrochemical separations, offering versatile structural tuning and fast electron transfer. First, through a judicious selection of polymer structure between a main‐chain metallopolymer (polyferrocenylsilane) and a pendant‐group metallopolymer (polyvinylferrocene), charge‐transfer interactions and binding strength toward competing metal ions are tuned, which as a result, dictate selectivity. For example, almost an order of magnitude increase in separation factor between chromate and meta‐vanadate can be achieved, depending on polymer structure. Second, these metallopolymer electrodes exhibit potential‐dependent selectivity that can even flip ion preference, based solely on electrical means—indicating a control parameter that is orthogonal to structural modifications. Finally, this work presents a framework for evaluating electrochemical separations in multicomponent ion mixtures and elucidates the underlying charge‐transfer mechanisms resulting in molecular selectivity through a combination of spectroscopy and electronic structure calculations. The findings demonstrate the applicability of redox‐metallopolymers in tailored electrochemical separations for environmental remediation, value‐added metal recovery, waste recycling, and even mining processing.

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