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1, 4, 5, 8‐naphthalene diimide (NDI)‐based MOFs, due to their tunable structures and properties, have shown promising applications in photochromism, photocatalysis, electrocatalysis, photothermal therapy, etc. Herein, using an L‐alanine modified NDI ligand, i.e. N, N′‐bis(L‐alanine)naphthalenediimide (AlaNDI), a novel Cd‐NDI Cd (AlaNDI)(H2O)]·DMF·H2O (complex 1) was constructed under solvothermal conditions, which has an obvious different structure with the previously reported ones. Structural analysis shows that the packing structure of complex 1 consists of two adjacent Cd atoms sharing two AlaNDI ligands, forming a dimetallic building block [Cd2O8]. Each building block connects a total of four AlaNDI ligands, where two Cd atoms are bridged by two ligands. The building blocks are interconnected by ligands to form a two‐dimensional layered structure. Based on the features of the NDI skeleton, it was found that complex 1 possesses multiple stimulus responses involving sensitivity to light: a reversible photochromism property and good photocatalytic degradation activity against various dyes, especially against cationic dyes crystal violet (CV), methyl violet (MV), and Janus green B (JGB). In addition, the stimulus‐response mechanism was investigated by control experiments. It is revealed that the photocatalytic active species may be related to h+ and •OH. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: The development of host‐guest MOF luminescent composites has attracted considerable attention. However, it is still a challenge to reasonably design large scale conjugated polycarboxylic acids metal‐organic framework (MOF) and modulate donor‐acceptor interaction. Herein, a series of isostructural 3D porous lanthanide MOF [Ln2(BINDI)0.5(NO3)(DMA)(H2O)]∙DMA∙2.5H2O (Ln = La (1), Ce (2), Pr (3) and Nd (4); H4BINDI (N,N'‐bis(5‐isophthalic acid)‐1,4,5,8‐naphthalenediimide) were synthesized. Considering the electron‐deficient performances of Ln‐BINDI MOFs, D‐A type composites Ln‐MOFs (1—4@H4TBAPy) were prepared via the incorporation of electron‐rich H4TBAPy (1,3,6,8‐tetrakis(p‐benzoic acid) pyrene), which more improved the luminescence performance of complexes 1—4 and can be used as fluorescence sensors for the detection of nitro compounds and aldehydes. High sensitivity of 1@H4TBAPy towards pNBA, pNA PNP, DNP, and TNP could be achieved through hydrogen bond interactions between MOF and analytes, as well as the π‐π interaction between H4TBAPy and the naphthalene ring of BINDI, thus the fluorescence quenching efficiency of 1@H4TBAPy was better than that of the complex 1. In addition, it is found that 1@H4TBAPy has high selectivity and sensitivity to aromatic aldehyde SA, 5‐Mesal and HMBA. Such strategy to enhance the emission of NDI based Ln‐BINDI MOFs, will open up an avenue to obtain more fluorescent MOFs for sensing. [ABSTRACT FROM AUTHOR]

Triazole polycarboxylic acid ligands are widely employed in the construction of MOFs due to their strong coordination ability and flexible coordination modes. In this work, three novel complexes (Pb(MCTCA)(H2O) (1), Co(HMCTCA)2(H2O)2 (2) and Cu(HMCTCA)2(H2O)2 (3)) based on the H2MCTCA ligand (5-methyl-1-(4-carboxyl)-1H-1,2,3-triazole-4-carboxylic acid) were successfully synthesized under hydrothermal conditions, respectively. X-ray single crystal structure analysis shows that complex 1 is a 3D network structure, where the central metal Pb(II) is six coordinated to form deformed triangular prism geometry. The complexes 2 and 3 are both 2D layer supramolecular structures connected through intermolecular hydrogen, where the central metals (Co/Cu) are six coordinated to form octahedral configuration geometry. Based on functional properties, it is found that complex 1 exhibits excellent detection ability for small-molecule drugs (azithromycin, colchicine and balsalazide disodium) and actinide cations (Th4+ and UO22+) within a lower concentration range without interference from other components. In particular, the detection limits of three small-molecule drugs are all lower than 0.30 μM. In addition, complexes 2 and 3 exhibited excellent catalytic reduction performance toward p-nitrophenol (PNP), with a reduction efficiency exceeding 98%. These experimental results evidence that complexes 1–3 have potential application prospects in fluorescence sensing and catalytic reduction. [ABSTRACT FROM AUTHOR]

Investigating the correlation between structural diversity and functionality serves as a pivotal factor in propelling the progress of functional materials, which however commonly needs tedious synthesis or sophisticated screening of conditions. Herein, we establish a facile strategy to synthesize two series of coordination networks (CNs, i.e., Ln-CMNDI and LN-CMNDI-F) with two distinct topologies using a solvent-directed method employing a specific ligand N,N′-bis(carboxymethyl)-1,4,5,8-naphthalenediimide (H2CMNDI) and rare-earth metal ions. The single-crystal X-ray diffraction analysis shows that Ln-CMNDI-F (Ln = La, Pr, Sm, Tb, Dy, Eu, Yb) synthesized using DMF and H2O as the solvents adopt a two-dimensional planar structure, while Ln-CMNDI (Ln= Ho, Gd, Tb, Yb, La and Eu) with three-dimensional supramolecular structures are obtained under the same conditions due to the existence of hydrogen bonding between molecules when DMF is replaced with DMA. The topology type of Ln-CMNDI-F is assigned as lcf (abbreviation of Ln-CMNDI-F) and the topological type of Ln-CMNDI is assigned as lcn (abbreviation of Ln-CMNDI) which are both not collected in the RCSR. Moreover, such differences in the changes of the topological structures lead to different optical properties including photochromism properties and fluorescence sensing abilities. The photochromism property of Ln-CMNDI-F is superior to that of Ln-CMNDI in terms of the speed of photoresponse. However, Ln-CMNDI exhibits a better performance in fluorescence sensing towards nitrophenols. This work reveals that Ln-CMNDI and Ln-CMNDI-F with novel topological structures can be constructed by adjusting the solvent reasonably, providing insights for the construction of CNs with promising optical applications. [ABSTRACT FROM AUTHOR]

A novel uranyl organic framework (U-hdpcp) based on flexible cyclic triphosphazene polycarboxylate ligands was prepared, which possesses the ability to sense aromatic aldehyde solutions (benzaldehyde, salicylaldehyde and 2-bromobenzaldehyde) and nitro compounds (2,4,6-trinitrophenol, 2,4-dinitrophenol and o-nitrophenol). A fluorescent thin film based on U-hdpcp@PVA with the ability to sense aldehyde vapors was prepared via a spin coating method. The work expands the library of UOF materials based on large-sized carboxylic acid ligands and demonstrates promising applications in the field of fluorescent sensors. [ABSTRACT FROM AUTHOR]