One-step separation of C2H4from ternary C2H2/C2H4/C2H6hydrocarbon mixtures is of great significance in the industry but is challenging due to the similar sizes and physical properties of C2H2, C2H4, and C2H6. Here, we report an anion-pillared hybrid ultramicroporous material, CuTiF6-TPPY, that has the ability of selective recognition of C2H4over C2H2and C2H6. The 4,6-connectedfscframework of CuTiF6-TPPY exhibits semi–cage-like one-dimensional channels sustained by porphyrin rings and TiF62−pillars, which demonstrates the noticeably enhanced adsorption of C2H2and C2H6over C2H4. Dynamic breakthrough experiments confirm the direct and facile high-purity C2H4(>99.9%) production from a ternary gas mixture of C2H2/C2H6/C2H4(1/9/90, v/v/v) under ambient conditions. Computational studies and in situ infrared reveal that the porphyrin moieties with large π-surfaces form multiple van der Waals interactions with C2H6; meanwhile, the polar TiF62−pillars form C–H•••F hydrogen bonding with C2H2. In contrast, the recognition sites for C2H4in the framework are less marked.

Adsorptive removal of trace SO2 emissions from flue‐gases can significantly reduce energy and water consumption and minimize the amount of unmanageable waste, however, this remains a great challenge. Herein, we report a universal strategy of chemical immobilization of amino acids into a robust metal–organic framework to enhance deep desulfurization. The grafted amino acid resulted in the formation of pores with compatible pore sizes and created abundant N‐containing moieties for selective SO2 adsorption. MOF‐808‐His (His = l‐histidine) exhibited a top‐ranking SO2 uptake (10.4 mmol g−1) with an excellent SO2/CO2 selectivity (90.5) under ambient conditions; furthermore, MOF‐808‐His could be easily regenerated. Breakthrough curves verified its excellent separation performances with water vapor and real flue‐gas compositions. Computational simulations confirmed the vital role of immobilized amino acids in improving the SO2 capture ability and selectivity. As a proof‐of‐concept, five natural amino acids were immobilized into MOF‐808; all samples displayed improved adsorptive desulfurization performances.

A mononuclar six-coordinate dysprosium complex was synthesized and structurally and magnetically characterized. X-ray structural analyses show trigonal-prismatic coordination geometry of the Dy center. Slow relaxation of magnetization in the absence of a direct-current field and magnetic hysteresis up to 3.0 K could be observed, indicating its single-ion-magnet behavior. Arrhenius fitting and ab initio calculations suggest that the magnetic relaxation process may not occur through the Orbach process at high temperatures under the experimental conditions.

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Dry desulfurization employing porous adsorbents is industrially preferred but efficient capture of sulfur dioxide (SO 2 ) at the ultralow concentration (i.e., 2000 ppm) is exceptionally challenging. Metal-organic frameworks with open metal sites (OMSs) can provide sufficient interactions with SO 2 , which, in turn, will degrade or compromise the structural robustness. Herein, we reported Cu-ATC that contains dense oppositely positioned Cu OMSs for efficient trace SO 2 removal. Explicitly, Cu-ATC adsorbs a benchmark amount of SO 2 (5.3 mmol g À1 ) at 0.01 bar with a record-high SO 2 storage density of 2.23 g cm À3 at ambient conditions. The critical role of OMSs has been confirmed by the partially desolvated sample with declined uptakes and adsorption enthalpy. The desulfurization performances have been validated by multicycle breakthrough experiments even with mimic flue-gas and water vapor. Computational simulations identify the adsorption sites at the molecular level. Combined with the high stability under various conditions, Cu-ATC is a potent candidate for industrial implementation.