SU-metal–organic frameworks: Bio-derived synthesis, structural diversity, and environmental applications

The development of sustainable metal–organic frameworks (MOFs) has been constrained by reliance on synthetically complex organic linkers. This review examines the “SU”(Stockholm University) series of MOFs, a family of porous materials derived from ellagic acid. This rigid, naturally abundant polyphenol is coordinated with Bismuth (III) or Zirconium (IV) ions. We critically analyse the structure-property relationships of three representative frameworks: SU-100, SU-101, and SU-102. Despite sharing the same organic linker, these materials show different behaviours driven by their metal nodes. SU-100 exhibits a breathing mechanism governed by flexible inorganic Bi O units rather than linker deformation, resulting in high selectivity for CO 2 and SF 6 separation. In contrast, SU-101solid phase is sized via a fully aqueous route and shows high chemical stability across a broad pH range (2–14), supporting its application in H 2 S chemisorption and solid-phase microextraction (SPME). Finally, the Zirconium-based SU-102 features an anionic framework with permanent porosity, where performance can be tuned via cation exchange to target emerging organic contaminants (EOCs). This review highlights how guest-directed synthesis and metal choice can unlock diverse topologies from a single natural ligand, illustrating how polyphenol-based MOFs can serve as alternatives to petrochemical-derived sorbents.