Perylenebisimide (PBI)-anthracene (AN)d onor-acceptor dyads/triad were prepared to investigate spin-orbit charge-transfer intersystem crossing (SOCT-ISC). Molecular conformation was controlled by connecting PBI units to the 2-or 9-position of the AN moiety.S teady-state, time-resolved transient absorption ande mission spectroscopy revealed that chromophore orientation, electronic coupling, and dihedrala ngle between donor and acceptor exert as ignificant effect on the photophysical property.T he dyad PBI-9-AN with orthogonal geometry shows weakg round-state coupling and efficient intersystem crossing (ISC, F D = 86 %) as compared with PBI-2-AN (F D = 57 %), which has am ore coplanar geometry.B yn anosecond transient absorption spectroscopy,along-lived PBI localized triplet state was observed (t T = 139 ms). Time-resolved EPR spectroscopy demonstratedt hat the electron spin polarization pattern of the triplet state is sensitive to the geometry and number of AN units attached to PBI.R eversible and stepwiseg eneration of near-IR-absorbing PBI radical anion (PBI À À•)a nd dianion (PBI 2À À)w as observed on photoexcitation in the presence of triethanolamine, and it was confirmed that selective photoexcitation at the near-IRa bsorption bands of PBIC À À is unable to produce PBI 2À À .

The tetracarboxylate ligand H4TBAPy based on the strongly fluorescent pyrene cores and bismuth iodide constructed a permanently 3D microporous fluorescent metal–organic framework Bi-TBAPy first . In this work, the photophysical properties, quantum yield, and lifetime of the framework were studied fully. Notably, Bi-TBAPy demonstrates unique “turn on” fluorescence sensing behavior toward biothiol molecules, for example, Cys, GSH, and Hcy. The limits of detections are 1.41 μM (Cys), 1.71 μM (GSH), and 1.10 μM (Hcy), respectively. Biological activity was studied by CCK-8, flow cytometry, and fluorescence microscopy. The experimental result will hopefully be useful information when using Bi-TBAPy as a fluorescent probe.

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Organic aromatic amines are widely used in various fields such as pharmaceuticals, pesticides, dyes, and tobacco smoke. The pollution of organic amines has become a problem that cannot be ignored, due to the extensive harmful effects on the environment and public health, which has become one of the most concerned frontier fields in the world. Identifying and microdetecting o-phenylenediamine (OPD), m-phenylenediamine (MPD), and p-phenylenediamine (PPD) using MOFs have rarely been reported. On the basis of the blue emission properties of Cu-TBDA constructed with 5,5′-((6-chloro-1,3,5-triazine-2,4-diyl)­bis­(azanediyl))­diisophthalic acid (H4TBDA) ligand, Cu-TBDA was studied primarily to identify and detect aromatic diamine family as a multifunctional chemical sensor. Interestingly, Cu-TBDA has a very high selectivity and sensitivity to OPD and MPD with a low limit of detection (5.00 μM for OPD and 1.77 μM for MPD). Especially for OPD, Cu-TBDA has a unique switching function for it. When the concentration of OPD is less than 9.1 × 10–4 M, the fluorescence response of Cu-TBDA suspension exhibit enhanced. However, when the concentration of OPD is more than 9.1 × 10–4 M, the emission intensity displays quenching phenomenon. Therefore, Cu-TBDA as a chemical sensor not only has recognition and detection functions for organic aromatic amines but also first exhibits turn-on and -off sensing behavior toward OPD.

The field of post‐synthesis modification has aroused widespread concern from diverse perspectives, including chemistry, biology, and material science. Post‐synthesis modification can introduce rich functionality into metal–organic frameworks (MOFs) without destroying the main structure of MOFs. Based on this research status, a series of lanthanide metal–organic frameworks ([Ln2(NH2‐BDC)2.5(CH3COO)(DMA)(H2O)]•DMA, Ln = Pr, Nd, Sm, Eu, Gd and Tb, NH2‐BDC = 2‐aminoterephthalic acid, DMA = N,N‐Dimethylacetamide) with 3D network structures, are synthesized by hydrothermal synthesis. Due to the presence of uncoordinated amino groups in the ligands, a series of post‐synthesis modified compounds are successfully synthesized through aldimine condensation reaction. Based on the good fluorescence properties and stable structure of coordination polymers and post‐synthesis modified compounds in water or organic solvents, they are able to be used as potential fluorescence sensor for the detection of Th4+, UO22+, and Cr2O72−, and the calculation result shows that the post‐synthesis modified compounds are more sensitive to the detection of analytes (Th4+, UO22+ and Cr2O72−) than coordination polymers. In addition, the MOF membrane prepared by self‐assembly of [Eu2(NH2‐BDC)2.5(CH3COO)(DMA)(H2O)]•DMA and ternary soap‐free copolymer (VAc‐AA‐BA) emulsion can be used first for detecting aldehyde vapors.