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For the first time, novel single-phase octahedral Bi3(FeO4)(WO4)2 (BFW) nanocrystals, as a visible-light-induced catalyst, had been successfully synthesized in a facile alkaline hydrothermal way without using any template. Scanning electron microscopy (SEM) images clearly show single crystals of BFW with regular octahedral morphology. The formation of the single-phase BFW compound was recorded using an X-ray diffraction (XRD) technique. The optical property of BFW was investigated using ultraviolet-visible light (UV-vis) spectra. The band-gap energy of BFW was revealed to be 1.98 eV. More importantly, the interfacial interaction of W6+ ions substituted by Fe3+ ions was confirmed. Moreover, the present study pointed out the positions of the valence band and the conduction band. Compared with the Bi2WO6 (BW) sample, BFW exhibited superior photocatalytic degradation activity of the Rhodamine B (RhB) under visible-light irradiation. A trapping experiment was conducted to further illustrate that hydroxyl radicals (•OH) played a distinct role among active species during the photodegradation of RhB. [ABSTRACT FROM AUTHOR]

Disclosedherein is a dehydrosilylative difluoroamidation of α-Csp3–H of tetrahydroisoquinolines with α,α-difluoro-α-TMS-acetamides.The process, which occurs at ambient temperature in the absence ofany transition metals, provides direct access to a broad range ofα,α-difluoroacetamide-substituted tertiary amine derivativesin high yields. Moreover, the method was successfully applied in theCsp3–H-directed difluorophosphorylation and difluorocarboxylationunder the same conditions. [ABSTRACT FROM AUTHOR]

Microscopic understanding of interaction between H2O and MAPbI3 (CH3NH3PbI3) is essential to further improve efficiency and stability of perovskite solar cells. A complete picture of perovskite from initial physical uptake of water molecules to final chemical transition to its monohydrate MAPbI3·H2O is obtained with in situ infrared spectroscopy, mass monitoring, and X-ray diffraction. Despite strong affinity of MA to water, MAPbI3 absorbs almost no water from ambient air. Water molecules penetrate the perovskite lattice and share the space with MA up to one H2O per MA at high-humidity levels. However, the interaction between MA and H2O through hydrogen bonding is not established until the phase transition to monohydrate where H2O and MA are locked to each other. This lack of interaction in water-infiltrated perovskite is a result of dynamic orientational disorder imposed by tetragonal lattice symmetry. The apparent inertness of H2O along with high stability of perovskite in an ambient environment provides a solid foundation for its long-term application in solar cells and optoelectronic devices. [ABSTRACT FROM AUTHOR]

The first example of decarboxylative difluoroacetamidation of aα,β-unsaturated carboxylic acids by using difluoromethyl-substituted carbonyl compounds was disclosed. The procedure, which was mediated by low-cost and benign CuSO4, furnished a broad range of difluorinated alkenes in remarkable yields with only the E configuration in most of the cases. Moreover, the product could be smoothly transformed to the corresponding difluorofunctionalized ester and alcohol in high yields. [ABSTRACT FROM AUTHOR]

The article presents information on heptamethine cyanine dyes. Heptamethine cyanine dyes employed as fluorescence labels and sensors of biomolecules in vivo have attracted immense interest because their spectra reach the near-infrared region, where a biological matrix exhibits the least absorption and autofluorescence background. However, most polymethine cyanine dyes have the fatal disadvantage that their Stokes shifts are less than 25 nm. The authors have synthesized two heptamethine cyanine dyes by introducing alkylamino groups at the central position. The new dyes are suggested to be a new paradigm for excited-state ICT. Significantly, they have a large Stokes shift and strong fluorescence which make them more suitable for use as fluorescence probes than do common cyanine dyes.