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Inspired by Nature, we present a polypeptide-based organic redox-active material constructed from renewable feedstocks, L-glutamic acid (an amino acid) and riboflavin (vitamin B2), to address challenges with start-to-end-of-life management in energy storage systems (ESSs). The amino acid was utilized to establish a degradable polymer backbone, along which many copies of riboflavin were incorporated to serve as the redox-active pendant groups that enabled energy storage. The overall synthesis involved the ring-opening polymerization (ROP) of anl-glutamic acid-derivedN-carboxyanhydride (NCA) monomer, followed by side chain activation with azides and, finally, click coupling to achieve installation of alkyne-functionalized riboflavin moieties. The steric bulkiness and rich chemical functionality of riboflavin resulted in synthetic complexities that required reaction optimization to achieve the desired polymer structure. Electrochemical characterization of the resultant riboflavin polypeptide, in organic electrolyte, showed quasireversible redox activity with a half-wave potential (E1/2) ofca.−1.10 Vvs.ferrocene/ferrocenium (Fc/Fc+). Cell viability assays revealed biocompatibility, as indicated by negligible cytotoxicity for fibroblast cells. The polypeptide design, consisting of labile amide backbone linkages and side-chain ester functionalities that tethered the riboflavin units to the backbone, enabled hydrolytic degradation to recover building blocks for future upcycling or recycling. This bioinspired strategy advances the development of degradable redox-active polymers and promotes sustainable materials design for circular energy storage technologies.
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This content will become publicly available on March 31, 2026
An Electrochemical Approach to Aluminum‐Based Redox Switchable Ring Opening Polymerization
Abstract We report the electrochemically switchable reactivity of (salfen)Al(OiPr) (salfen = 1,1′‐di(2,4‐bis‐tert‐butyl‐salicylimino)ferrocene) toward the ring‐opening polymerization of various cyclic esters, ethers, and carbonates. Using a recently developed electrochemical system comprised of an H‐cell and a glassy carbon working electrode, an applied potential can alternate between the two redox states of the catalyst and alter monomer incorporation during ring‐opening polymerization. We discuss differences in activity and control under electrochemical conditions compared to previously studied chemical redox methods and discuss the necessity of a redox switch during certain copolymerization reactions.
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- Award ID(s):
- 2400314
- PAR ID:
- 10593837
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- ChemCatChem
- Volume:
- 17
- Issue:
- 9
- ISSN:
- 1867-3880
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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