Simple Access to Sol-Gel Precursors Bearing Fluorescent Aromatic Core Units

Improving Photophysical Properties and Hydrophily of Conjugated Polymers Simultaneously by Side-Chain Modification for Near-Infrared Cell Imaging

Conjugated polymers (CPs)-based near-infrared phototheranostics are receiving increasing attention due to their high molar extinction coefficient, wide emission wavelength, easy preparation and excellent biocompatibility. Herein, several new conjugated polymers with D2-D1-A structures were easily prepared through one-pot coupling using triphenylamine (D2) as well as thiophenes (D1) as electron donors and benzothiadiazole (A) as electron acceptors. Interesting, their optical performance and power conversion efficiency could be tuned by side chains on thiophenes (D1). The introduction of ethylenedioxy into D1 as side chain significantly improves fluorescence imaging brightness, photothermal conversion efficiency and hydrophilicity, and extends emission wavelength, which are beneficial for phototheranostic. The side chain modification provides new opportunity to design efficient phototheranostics without construction new fluorescent skeletons.

Crystal structure of 5,6-diphenyldibenzo[c, g]chrysene, C38H24

C38H24, monoclinic, C2/c (no. 15), a = 37.6829(14) Å, b = 7.4695(3) Å, c = 17.4881(7) Å, β = 95.269(3)°, V = 4901.6(3) Å3, Z = 8, R gt(F) = 0.0472, wR ref(F 2) = 0.1177, T = 123(2) K.

Alternating Tetrafluorobenzene and Thiophene Units by Direct Arylation for Organic Electronics

Direct arylation represents an attractive alternative to the conventional cross-coupling methods because of its step-economic and eco-friendly advantages. A set of simple D-A oligomeric molecules (F-3, F-5, and F-7) by integrating thiophene (T) and tetrafluorobenzene (F4B) as alternating units through a direct arylation strategy is presented to obtain high-performance charge-transporting materials. Single-crystal analysis revealed their herringbone packing arrangements driven by intensive C-H⋅⋅⋅π interactions. An excellent hole-transporting efficiency based on single-crystalline micro-plates/ribbons was witnessed, and larger π-conjugation and D-A constitution gave higher mobilities. Consequently, an average mobility of 1.31 cm²  V^-1  s^-1 and a maximum mobility of 2.44 cm²  V^-1  s^-1 for F-7 were achieved, providing an effective way to obtain high-performance materials by designing simple D-A oligomeric systems.

Crystal structure of 2-(4-(dimethylamino)phenyl)-10-methylacridin-9(10H)-one, C22H20N2O

C22H20N2O, monoclinic, P21/n (no. 14), a = 8.316(2) Å, b = 9.247(2) Å, c = 20.908(5) Å, β = 93.538(5)°, V = 1604.7(7) Å3, Z = 4, Rgt(F) = 0.0618, wRref(F2) = 0.1527, T = 173(2) K.

Crystal structure of 2-bromo-7-(4-(dimethylamino)phenyl)-10-methylacridin-9 (10H)-one, C22H19BrN2O

C22H19BrN2O, monoclinic, P21/n (no. 14), a = 8.0338(16) Å, b = 9.0803(18) Å, c = 24.281(5) Å, β = 95.78(3)°, V = 1762.28(60) Å3, Z = 4, Rgt(F) = 0.0871, wRref(F2) = 0.1595, T = 173(2) K.

Photoemission Studies on N-Substituted Dithienylated Phenothiazines

Dithienylated phenothiazines (DTPTs) with different functional groups attached to the central nitrogen atom are presented as a class of versatile metal-free chromophores for the design of dye-sensitized solar cells (DSSCs) and organic light-emitting diodes (OLEDs). The electronic characteristics of spin-coated thin films on polycrystalline gold were studied using photoelectron spectroscopy assisted by theoretical calculations, scanning force microscopy, and UV/Vis spectroscopy. Complementary fluorescence spectra show light emission in the blue region (465 nm). The absorption properties and good hole-transporting abilities make DTPTs feasible hole-transporting materials (HTM) and metal-free chromophores in UV-sensitive solar cell designs.

Breathing some new life into an old topic: chalcogen-nitrogen π-heterocycles as electron acceptors

Recent progress in the design, synthesis and characterization of chalcogen-nitrogen π-heterocycles, mostly 1,2,5-chalcogenadiazoles (chalcogen: S, Se and Te) and their fused derivatives, possessing positive electron affinity is discussed together with their use in preparation of charge-transfer complexes and radical-anion salts-candidate building blocks of molecule-based electrical and magnetic functional materials.

Efficient conversion of arylene precursors into photoluminescent phosphonates for surface modification of metal oxides

Three highly fluorescent phosphonates have been prepared in good yields from different arylene bridged 5-iodothiophenes by following an optimized four-step procedure. The compounds have been immobilised on mesoporous zirconia, alumina and titania particles in order to probe their luminescence properties on the surfaces. The organic compounds as well as the obtained hybrid materials have been characterised using liquid phase or MAS NMR spectroscopy, N2 physisorption measurements, ATR-IR spectroscopy and elemental analysis. The luminescence intensity of the organic molecules was found to be in general much more dependent on the surface used for grafting rather than on the dye loading obtained for different metal oxides powders. The luminescence extinction, which has been detected for all coated TiO2 samples, is most likely due to the different electronic properties of this semiconducting support compared to the other surfaces. The method described shows how fluorescent tracers can be easily synthesised and applied in surface analytics after exploring the interaction of the corresponding organophosphonates with several ceramic interfaces.