3D-Printed Porous Supramolecular Sorbents for Cobalt Recycling

Abstract

Electronic waste recycling is a recognized global challenge that requires new strategies to bind and release critical materials selectively, such as cobalt present in lithium-ion batteries. To address this challenge, hierarchical 3D-printed porous polymer scaffolds bearing supramolecular receptors were prepared using vat photopolymerization and their cobalt binding profiles were examined as a function of matrix polarity. By combining highresolution digital light processing (DLP) with polymerizationinduced phase separation (PIPS), functional acrylic copolymer networks with micrometer-level precision of geometry and nanometer-level pores were generated. Covalent integration of a methacrylate-functionalized bisdicyclohexyl acetamide (BDCA-MA) receptor enabled binding and release of cobalt(II) chloride (CoCl 2 ) via a solvent polarity switch mechanism involving a change in solvent from ethanol to water. The present structures proved reusable as shown by sustained high binding efficiency over five bind and release cycles. This platform represents a "green" and energy conscious method for future electronic waste recycling.

Thermally Driven Catch-and-Release of CoCl2

“…Our group previously demonstrated that a glycolamide-based receptor with an all-oxygen tetradentate structure exhibits affinity for lithium and cobalt in anhydrous solvents. Given the limitations associated with anhydrous solvents, we were keen to explore whether cobalt capture and release could be achieved in 95% ethanol.…”