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Based on the electron‐withdrawing effect of the Pt(bpy)Cl2 molecule, a simple post‐modification amide reaction was firstly used to graft it onto the surface of NH2‐MIL‐125, which performed as a highly efficient electron acceptor that induced the conversion of the photoinduced charge migration pathway from internal BDC→TiOx migration to external BDC→PtNx migration, significantly improving the efficiency of photoinduced electron transfer and separation. Furthermore, precisely regulating over the first coordination sphere of Pt single atoms was achieved using further post‐modification with additional bipyridine to investigate the effect of Pt−Nx coordination numbers on reaction activity. The as‐synthesized NML‐PtN2 exhibited superior photocatalytic hydrogen evolution activity of 7.608 mmol g−1 h−1, a remarkable improvement of 225 and 2.26 times compared to pristine NH2‐MIL‐125 and NML‐PtN4, respectively. In addition, the superior apparent quantum yield of 4.01 % (390 nm) and turnover frequency of 190.3 h−1 (0.78 wt % Pt SA; 129 times compared to Pt nanoparticles/NML) revealed the high solar utilization efficiency and hydrogen evolution activity of the material. And macroscopic color changes caused by the transition of carrier migration paths was first observed. It holds profound significance for the design of MOF‐Molecule catalysts with efficient charge carrier separation and precise regulation of single‐atom coordination sphere. [ABSTRACT FROM AUTHOR]

Lanthanide metal–organic frameworks (Ln‐MOFs) are promising for luminescence detection of volatile organic compound (VOC) vapors, but usually suffer from the silent or quenched Ln3+ emission. Herein, we report a new dual‐emissive Eu‐MOF composed of the coordinatively unsaturated Eu9 clusters that afford abundant open metal sites to form a confined "binding pocket" to facilitate the preconcentration and recognition of VOCs. Single‐crystal structural analyses reveal that specific analytes can replace the OH oscillators in the first coordination sphere of Eu3+ and form a unique hydrogen‐bonding second‐sphere adduct tying adjacent Eu9 clusters together to minimize their nonradiative vibrational decay. With the promoted Eu3+ luminescence, the MOF realizes real‐time in situ visual sensing of THF vapor (<1 s) and shows a quantitative ratiometric response to the vapor pressure with a limit of detection down to 17.33 Pa. Also, it represents a top‐performing ratiometric luminescent thermometer. [ABSTRACT FROM AUTHOR]

The separation of n‐alkanes from their branched isomers is vitally important to improve octane rating of gasoline. To facilitate mass transfer, adsorptive separation is usually operated under high temperatures in industry, which require considerable energy. Herein, we present a kind of dynamic pillar‐layered MOF that exhibits self‐adjustable structure and pore space, a behavior induced by guest molecules. A combination of the flexibility of the framework with the commensurate adsorption for n‐hexane results in exceptional performance in separating hexane isomers. More significantly, lower temperature prompts the guest molecules to open the dynamic pores, which may provide a new perspective for optimized separation performance at lower temperatures with less energy consumption. [ABSTRACT FROM AUTHOR]

Although great achievements have been made in the synthesis of giant lanthanide clusters, novel structural models are still scarce. Herein, we report a giant lanthanide cluster Dy76, constructed from [Dy3(μ3‐OH)4] and [Dy5(μ4‐O)(μ3‐OH)8] building blocks. As the largest known Dy cluster, the structure of Dy76 can be seen as arising from the fusion of two Dy48 clusters; these clusters can be isolated under various synthetic conditions and were characterized by single‐crystal X‐ray diffraction. This new, fused structural model of the pillar motif has not been found in Ln clusters. Furthermore, the successful conversion of Dy76 back into Dy48 in a retrosynthetic manner supports the proposed fusion formation mechanism of Dy76. Electrospray ionization mass spectrometry (ESI‐MS) analysis suggests that the metal cluster skeleton of Dy76 shows good stability in various solvents. This work not only reveals a new structural type of Ln clusters but also provides insight into the novel fusion assembly process. [ABSTRACT FROM AUTHOR]

A mixed molecular building block (MBB) strategy for the synthesis of double-walled cage-based porous metal-organic frameworks (MOFs) is presented. By means of this method, two isostructural porous MOFs built from unprecedented double-walled metal-organic octahedron were obtained by introducing two size-matching C3-symmetric molecular building blocks with different rigidities. With their unique framework structures, these MOFs provide, to the best of our knowledge, the first examples of double-walled octahedron-based MOFs. [ABSTRACT FROM AUTHOR]