Evolution from [Zn₉] to a record-high [Zn₅₄] subblock and engineering a hierarchical supramolecular framework for enhanced iodine uptake

Hierarchical supramolecular frameworks are being designed and constructed for various applications, yet the controlled assembly and process understanding incorporating giant building blocks remains a great challenge. Here, we report a strategy of "rivet" substitution and "hinge" linkage for the controlled assembly of the hierarchical supramolecular framework. The replacement of two "rivet" ethylene glycol (EG) molecules for triangular prism [Zn₉] (a small block in 1) with a 1,3-propanediol (PDO) provides space for a "hinge" linkage from adjacent ligands, thus providing a hierarchical (from micro- to mesopores, from the internal cavity to external surface) supramolecular framework (2) based on a coordinative subblock with the record number of zinc ions ([Zn₅₄]). Time-dependent powder X-ray diffraction and ESI-MS technology were used to assess the <i>in situ</i> evolution process: logically progressing from [Zn₉] to [Zn₁₈], then to [Zn₂₇], and finally to [Zn₅₄]. The sequential transformation entails two types of half-opening cavities and two types of internal microcages. Further aggregation of [Zn₅₄] in dia topology engenders the formation of a one-dimensional channel (10 Å), and an additional mesocage with a volume of 16 × 16 × 55 ų. The diverse pore system exhibits an impressive uptake capability (3.19 g g^-1) for iodine vapor at 75 °C and effective ethylene purification. Our investigations represent a valuable avenue for assembling a giant subblock and hierarchical supramolecular framework, facilitating multi-functional molecular accommodation.