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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 [Zn 9 ] (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 ([Zn 54 ]). Time-dependent powder X-ray diffraction and ESI-MS technology were used to assess the in situ evolution process: logically progressing from [Zn 9 ] to [Zn 18 ], then to [Zn 27 ], and finally to [Zn 54 ]. The sequential transformation entails two types of half-opening cavities and two types of internal microcages. Further aggregation of [Zn 54 ] in dia topology engenders the formation of a one-dimensional channel (10 Å), and an additional mesocage with a volume of 16 × 16 × 55 Å 3 . 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., Competing Interests: The authors declare no conflict of interest., (This journal is © The Royal Society of Chemistry.)

The adsorptive separation of ternary propyne (C 3 H 4 )/propylene (C 3 H 6 )/propane (C 3 H 8 ) mixtures is of significant importance due to its energy efficiency. However, achieving this process using an adsorbent has not yet been accomplished. To tackle such a challenge, herein, we present a novel approach of fine-regulation of the gradient of gate-opening in soft nanoporous crystals. Through node substitution, an exclusive gate-opening to C 3 H 4 (17.1 kPa) in NTU-65-FeZr has been tailored into a sequential response of C 3 H 4 (1.6 kPa), C 3 H 6 (19.4 kPa), and finally C 3 H 8 (57.2 kPa) in NTU-65-CoTi, of which the gradient framework changes have been validated by in situ powder X-ray diffractions and modeling calculations. Such a significant breakthrough enables NTU-65-CoTi to sieve the ternary mixtures of C 3 H 4 /C 3 H 6 /C 3 H 8 under ambient conditions, particularly, highly pure C 3 H 8 (99.9%) and C 3 H 6 (99.5%) can be obtained from the vacuum PSA scheme. In addition, the fully reversible structural change ensures no loss in performance during the cycling dynamic separations. Moving forward, regulating gradient gate-opening can be conveniently extended to other families of soft nanoporous crystals, making it a powerful tool to optimize these materials for more complex applications., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)