Flexible metal–organic framework (MOF) adsorbents commonly encounter limitations in removing trace impurities below gate-opening threshold pressures. Topology reconfiguration can fundamentally eliminate intrinsic structural flexibility, yet remains a formidable challenge and is rarely achieved in practical applications. Herein, a solvent-mediated approach is presented to regulate the flexible CuSnF₆-dpds-sql (dpds = 4,4′'-dipyridyldisulfide) with sql topology into rigid CuSnF₆-dpds-cds with cds topology. Notably, the cds topology is unprecedented and first obtained in anion-pillared MOF materials. As a result, rigid CuSnF₆-dpds-cds exhibits enhanced C₂H₂ adsorption capacity of 48.61 cm³ g⁻¹ at 0.01 bar compared to flexible CuSnF₆-dpds-sql (21.06 cm³ g⁻¹). The topology transformation also facilitates the adsorption kinetics for C₂H₂, exhibiting a 6.5-fold enhanced diffusion time constant (D/r²) of 1.71 × 10⁻³ s⁻¹ on CuSnF₆-dpds-cds than that of CuSnF₆-dpds-sql (2.64 × 10⁻⁴ s⁻¹). Multiple computational simulations reveal the structural transformations and guest–host interactions in both adsorbents. Furthermore, dynamic breakthrough experiments demonstrate that high-purity C₂H₄ (>99.996%) effluent with a productivity of 93.9 mmol g⁻¹ can be directly collected from C₂H₂/C₂H₄ (1/99, v/v) gas-mixture in a single CuSnF₆-dpds-cds column.

中文翻译：

---

阴离子柱金属有机框架从柔性到刚性的拓扑重构以增强乙炔分离


柔性金属有机骨架（MOF）吸附剂在去除低于闸门开启阈值压力的痕量杂质时通常会遇到限制。拓扑重构可以从根本上消除固有的结构灵活性，但仍然是一个艰巨的挑战，并且在实际应用中很少实现。在此，提出了一种溶剂介导的方法，将具有 sql 拓扑的柔性 CuSnF ₆ -dpds-sql (dpds = 4,4''-dipyridyldisulfide) 调节为刚性 CuSnF ₆ -具有 CD 拓扑的 dpds-cd。值得注意的是，cds 拓扑是前所未有的，并且首次在阴离子柱 MOF 材料中获得。结果，刚性 CuSnF ₆ -dpds-cds 表现出增强的 C ₂ H ₂ 吸附容量，达到 48.61 cm ³ g ⁻¹ 与柔性 CuSnF ₆ -dpds-sql (21.06 cm ³ g ⁻¹ ) 相比，压力为 0.01 bar。拓扑变换还促进了 C ₂ H ₂ 的吸附动力学，扩散时间常数 (D/r ² ) 增强了 6.5 倍，为 1.71 × CuSnF ₆ -dpds-cds 上的 ⁻³ s ⁻¹ 比 CuSnF ₆ -dpds-sql (2.64 × 10 ⁻⁴ s ⁻¹ ）。多次计算模拟揭示了两种吸附剂的结构转变和客体相互作用。此外，动态突破实验表明，可以直接收集高纯度的 C ₂ H ₄ (>99.996%) 流出物，生产率为 93.9 mmol g ⁻¹ 来自 C ₂ H ₂ /C ₂ H ₄ (1/99, v/v) 单一 CuSnF 气体混合物 ₆ -dpds-cds 列。