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Herein, chiral metal–organic frameworks (MOFs), DCF-20 and LCF-20, were utilized as matrices for both chirality transfer and energy transfer. HBT1@MOFs and HBT2@MOFs emit excitation-dependent circularly polarized luminescence (CPL) due to excited-state intramolecular proton transfer (ESIPT). HBT1/C152/NIR@MOFs exhibit full-color and white CPL. The luminescence dissymmetry factors (glum) were significantly increased, benefiting from the efficient chirality space transfer and high luminescence efficiency. [ABSTRACT FROM AUTHOR]

Triply interlocked [2]catenane complexes featuring two identical, mechanically interlocked units are extraordinarily rare chemical compounds, whose properties and applications remain open to detailed studies. Herein, we introduce the rational design of a new ligand precursor, L1, suitable for the synthesis of six triply interlocked [2]catenanes by coordination‐driven self‐assembly. The interlocked compounds can be reversibly converted into the corresponding simple triangular prism metallacage by addition of H2O or DMF solvents to their CH3OH solutions, thereby demonstrating the importance of π⋅⋅⋅π stacking and hydrogen bonding interactions in the formation of triply interlocked [2]catenanes. Moreover, extensive studies have been conducted to assess the remarkable photothermal conversion performance. Complex 6 a, exhibiting outstanding photothermal conversion performance (conversion efficiency in solution : 31.82 %), is used to prepare novel photoresponsive elastomer in combination with thermally activated liquid crystal elastomer. The resultant material displays robust response to near‐infrared (NIR) laser and the capability of completely reforming the shape and reversible actuation, paving the way for the application of half‐sandwich organometallic units in photo‐responsive smart materials. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: The crystallization of chiral molecules is of great significance to understand the origin and evolution of hierarchical chirality and reveal the relationships between structural chirality and circularly polarized luminescence (CPL) activity. Here, we report two pairs of chiral metal–organic frameworks (MOFs) (DCF‐17/LCF‐17, DCF‐18/LCF‐18) by utilizing tetradentate ligands tetra(3‐imidazoylphenyl)ethylene (TIPE) and 4,4'‐[4',5'‐bis[4‐(4‐pyridinyl)phenyl][1,1':2',1"‐terphenyl]‐4,4"‐diyl]bis[pyridine] (TPPP) as linkers. It can be observed that the spontaneous resolution of the achiral ligands is converted into the induced resolution, and the ligands form the absolute configuration by using enantiopure camphoric acid (cam) as chiral induced reagent (CIR). As a result, the racemate MOFs can be driven to generate absolute homochiral crystallization. Another two achiral MOFs [Cd(D‐cam)(TPPP)0.5] (AF‐1, AF = achiral framework) and [Cd(L‐cam)(TPPP)0.5] (AF‐2) were prepared. The position disorder of D/L‐cam skeleton causes the generation of nonchiralization, further leading to disappearance of symmetry breaking of TPPP. For the perspective of structure, this is the first report which reveals the chiral transfer and nonchiralization between chiral induced agents and tetradentate ligands. Besides, DCF‐17 and LCF‐17 show CPL with luminescence dissymmetry factor (glum) of –1.0 × 10‐2 and +9.2 × 10–3, respectively. This work provides the useful evidences to reveal the induced chiral crystallization and the construction of CPL‐active crystalline materials. [ABSTRACT FROM AUTHOR]

Lanthanide metal–organic framework (Ln-MOF) based phosphors for light-emitting diodes (LEDs) play an important role in the fields of solid-state lighting and display. The rational design of organic antennae to address the drawback of low extinction coefficients of the lanthanide ions is highly desired. In this work, we provide a new design strategy to achieve an energy transfer molecule with a through-space conjugated folded structure, which can strengthen the skeleton rigidity and facilitate triplet state energy transfer. Consequently, one U-type π-conjugated molecule 2,6-bis(3,5-dicarboxylphenoxy) pyridine (H4L) was selected as a light gatherer to sensitize lanthanide ions for the construction of Ln-MOFs [Ln(HL)(H2O)3]n (Eu-MOF and Tb-MOF), which exhibit a long-lived luminescence lifetime (0.88 ms for Eu-MOF and 1.31 ms for Tb-MOF) and high quantum yields (50.87% for Eu-MOF and 85.64% for Tb-MOF). Furthermore, a white LED device with a colour rendering index (89) was fabricated using the mixture of Ln-MOFs with a commercial blue phosphor. [ABSTRACT FROM AUTHOR]

A broad light-harvesting range and efficient charge separation are two main ways to enhance the visible photocatalytic performance of semiconductors. Herein, an ionic porphyrin MOF [In(TPyP)]·(NO3) (1) (TPyP = 5,10,15,20-tetrakis(4-pyridyl)-21H,23H-porphyrin) was synthesized via in situ metalation. The orderly arranged porphyrin photosensitizer and the internal electric field between the MOF host and NO3− guests enable effective visible light response and electron–hole separation. Consequently, the as-synthesized MOF shows efficient photocatalytic degradation of rhodamine B (RhB), methyl orange (MO) and methylene blue (MB) organic pollutants. It can degrade 99.07% of RhB within only 20 minutes under visible light irradiation (λ > 420 nm) with a high chemical reaction rate constant of 0.2400 min−1. The photocatalytic activity of the title MOF is more efficient than those of other reported MOFs, COFs and even inorganic semiconductors. The reusability, energy level, band gap, charge distribution and main degradation mechanisms of the photocatalyst were well studied. [ABSTRACT FROM AUTHOR]