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Afterglow materials have garnered significant interest due to distinct photophysical characteristics. However, it is still difficult to achieve long afterglow phosphorescence from organic molecules due to aggregation-caused quenching (ACQ) and energy dissipation. In addition, most materials reported so far have long afterglow emission only at room or even low temperatures, and mainly use UV light as an excitation source. In this work, we report a strategy to achieve high temperature long afterglow emission through the assembly of isolated 0D metal-organic cages (MOCs). In which, both ACQ and phosphorescence quenching effects are effectively mitigated by altering the stacking mode of organic chromophores through orthogonally anchoring into the edges of cubic MOCs. Furthermore, improvement in molecular rigidity, promotion of spin-orbit coupling and broadening of the absorption range are achieved through the MOC-engineering strategy. As a result, we successfully synthesized MOCs that can produce afterglow emission even after excitation by WLEDs at high temperatures (380 K). Moreover, the MOCs are capable of generating afterglow emissions when excited by mobile phone flashlight at room temperature. Given these features, the potential applications of MOCs in the visual identification of explosives, information encryption and multicolor display are explored., (© 2024 Wiley-VCH GmbH.)

A series of isostructural supramolecular cages with a rhombic dodecahedron shape have been assembled with distinct metal-coordination lability (M 8 Pd 6 -MOC-16, M=Ru 2+ , Fe 2+ , Ni 2+ , Zn 2+ ). The chirality transfer between metal centers generally imposes homochirality on individual cages to enable solvent-dependent spontaneous resolution of Δ 8 /Λ 8 -M 8 Pd 6 enantiomers; however, their distinguishable stereochemical dynamics manifests differential chiral phenomena governed by the cage stability following the order Ru 8 Pd 6 >Ni 8 Pd 6 >Fe 8 Pd 6 >Zn 8 Pd 6 . The highly labile Zn centers endow the Zn 8 Pd 6 cage with conformational flexibility and deformation, enabling intrigue chiral-Δ 8 /Λ 8 -Zn 8 Pd 6 to meso-Δ 4 Λ 4 -Zn 8 Pd 6 transition induced by anions. The cage stabilization effect differs from inert Ru 2+ , metastable Fe 2+ /Ni 2+ , and labile Zn 2+ , resulting in different chiral-guest induction. Strikingly, solvent-mediated host-guest interactions have been revealed for Δ 8 /Λ 8 -(Ru/Ni/Fe) 8 Pd 6 cages to discriminate the chiral recognition of the guests with opposite chirality. These results demonstrate a versatile procedure to control the stereochemistry of metal-organic cages based on the dynamic metal centers, thus providing guidance to maneuver cage chirality at a supramolecular level by virtue of the solvent, anion, and guest to benefit practical applications., (© 2023 Wiley-VCH GmbH.)

Porous supramolecular assemblies constructed by noncovalent interactions are promising for adsorptive purification of methane because of their easy regeneration. However, the poor stability arising from the weak noncovalent interactions has obstructed their practical applications. Here, we report a robust and easily regenerated polyhedron-based cationic framework assembled from a metal-organic square. This material exhibits a very low affinity for CH 4 and N 2 , but captures other competing gases (e.g. C 2 H 6 , C 3 H 8 , and CO 2 ) with a moderate affinity. These results underpin highly selective separation of a range of gas mixtures that are relevant to natural gas and industrial off-gas. Dynamic breakthrough studies demonstrate its practical separation for C 2 H 6 /CH 4 , C 3 H 8 /CH 4 , CO 2 /N 2 , and CO 2 /CH 4 . Particularly, the separation time is ≈11 min g -1 for the C 2 H 6 /CH 4 (15/85 v/v) mixture and ≈49 min g -1 for the C 3 H 8 /CH 4 (15/85 v/v) mixture (under a flow of 2.0 mL min -1 ), respectively, enabling its capability for CH 4 purification from light alkanes., (© 2022 Wiley-VCH GmbH.)