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In this study, we synthesized a coumarin–hemicyanine-based deep red fluorescent dye that exhibits an intramolecular charge transfer (ICT). The probe had a large Stokes shift of 287 nm and a large molar absorption coefficient (ε = 7.5 × 105 L·mol−1·cm−1) and is best described as a deep red luminescent fluorescent probe with λem = 667 nm. The color of probe W changed significantly when it encountered cyanide ions (CN−). The absorption peak (585 nm) decreased gradually, and the absorption peak (428 nm) increased gradually, so that cyanide (CN−) could be identified by the naked eye. Moreover, an obvious fluorescence change was evident before and after the reaction under irradiation using 365 nm UV light. The maximum emission peak (667 nm) decreased gradually, whilst the emission peak (495 nm) increased gradually, which allowed for the proportional fluorescence detection of cyanide (CN−). Using fluorescence spectrometry, the fluorescent probe W could linearly detect CN− over the concentration range of 1–9 μM (R2 = 9913, RSD = 0.534) with a detection limit of 0.24 μM. Using UV-Vis spectrophotometry, the linear detection range for CN− was found to be 1–27 μM (R2 = 0.99583, RSD = 0.675) with a detection limit of 0.13 μM. The sensing mechanism was confirmed by 1H NMR spectroscopic titrations, 13C NMR spectroscopy, X-ray crystallographic analysis and HRMS. The recognition and detection of CN− by probe W was characterized by a rapid response, high selectivity, and high sensitivity. Therefore, this probe provides a convenient, effective and economical method for synthesizing and detecting cyanide efficiently and sensitively. [ABSTRACT FROM AUTHOR]

LaFeO3/NiO modified g-C3N4 nanosheets (L-N/CNS) were synthesized by a two-step method. HRTEM results showed that an intimate contact between LaFeO3, NiO and N-CNS was successfully established. Ninety percent of phenol was degraded within 120 min, and the hydrogen evolution rate of 171.2 μ mol h − 1 g − 1 was obtained over the L-N/CNS heterojunctions under the visible-light irradiation. It was higher than that of g-C3N4 nanosheets, NiO modified g-C3N4 and LaFeO3/g-C3N4. The ⋅ O 2 − radicals acted the crucial role in the photocatalytic degradation reaction. EIS, PL and time-resolved fluorescence spectra demonstrated that L-N/CNS possessed the highest charge separation efficiency. The intimate contact between LaFeO3, NiO and g-C3N4 nanosheets promoted the separation and transfer of photo-induced electron–hole pairs and consequently prolonged the exciton lifetime, and implied more photo-induced electrons could be probably involved in the photocatalytic reactions on the surface of photocatalysts. Thus, the visible-light driven photocatalytic performances of L-N/CNS were effective. This work provided a feasible method to design and construct heterostructures for the exploitation of solar energy. In this study, LaFeO3/NiO modified porous g-C3N4 nanosheets were synthesized by a two-step method. HRTEM results showed that an intimate contact between LaFeO3, NiO and N-CNS was successfully established. A total of 90% of phenol was degraded within 120 min, and the hydrogen evolution rate of 171.2 μmol h–1 g–1 was obtained over the LaFeO3/NiO modified porous g-C3N4 nanosheets heterojunctions under the visible light irradiation. [ABSTRACT FROM AUTHOR]

A phenazine-1-carboxylic acid intermediate was synthesized from the reaction of aniline and 2-bromo-3-nitro-benzoic acid. It was then esterified and reacted with hydrazine hydrate to afford phenazine-1-carboxylic hydrazine. Finally, 10 new hydrazone compounds 3a–3j were obtained by the condensation reaction of phenazine-1-carboxylic acid hydrazide and the respective aldehyde-containing compound. The structures were characterized by 1H and 13C NMR spectroscopy, MS and single crystal X-ray diffraction. The antitumor activity of the target compounds in vitro (HeLa and A549) was determined by thiazolyl blue tetrazolium bromide. The results showed that compound (E)-N′-(2-hydroxy-4-(2-(piperidine-1-yl) ethoxy) benzyl) phenazine-1-carbonyl hydrazide 3d exhibited good cytotoxic activity. [ABSTRACT FROM AUTHOR]

Mesoporous LaFeO3/g-C3N4 Z-scheme heterojunctions (LFC) were synthesized via the incorporation of LaFeO3 nanoparticles and porous g-C3N4 ultrathin nanosheets. The as prepared LFC were characterized by transmission electron microscopy, scanning electron microscopy, atomic force microscopy, X-ray photoelectron spectroscopy, powder X-ray diffraction, Raman spectra and N2 adsorption analysis. The structural analysis indicated that the reheating process and the addition of NH4Cl in the thermal polymerization were the key factors to get porous g-C3N4 ultrathin nanosheets and to obtain high specific surface areas of LFC. It remarkably enhanced the adsorption capacity and photocatalytic degradation of LFC for removal of oxytetracycline (OTC). The effect of the mass percentage of LaFeO3 in LFC, pH and temperature on the OTC adsorption was investigated. The LaFeO3/g-C3N4 heterojunction with 2 wt % LaFeO3 (2-LFC) exhibited highest saturated adsorption capacity (101.67 mg g−1) and largest photocatalytic degradation rate constant (1.35 L g−1 min−1), which was about 9 and 5 times higher than that of bulk g-C3N4 (CN), respectively. This work provided a facile method to prepare mesoporous LaFeO3/g-C3N4 heterojunctions with especially well adsorption and photocatalytic activities for OTC, which can facilitate its practical applications in pollution control. [ABSTRACT FROM AUTHOR]

A facile hot injection approach to synthesize high-quality non-stoichiometric ZnxAgyInS1.5+x+0.5y nanocrystals (NCs) in the size range of 2.8–3.1 nm was presented. The fluorescence spectra had single band gap features, and indicated the formation of alloy states rather than simple composite structures. The chemical compositions, photoluminescence (PL) emission wavelengths, and quantum yields of ZnxAgyInS1.5+x+0.5y nanocrystals were significantly influenced by the concentration of an organic capping agent. The appropriate proportion of 1-dodecanthiol in the precursor prevented the precipitation, increased the fluorescence quantum yield, and improved their optical properties. The proper ratio of capping agent allowed Zn, Ag, and In to form a better crystallinity and compositional homogeneity of ZnxAgyInS1.5+x+0.5y nanocrystals. The photoluminescence was tunable from blue to red in the range of 450–700 nm as the Ag content changed independently. The PL and absorption spectra of ZnxAgyInS1.5+x+0.5y nanocrystals showed a significant blue shift with the decrease of Ag content in the precursor. As there were no obvious differences on the average particle sizes of ZnxAgyInS1.5+x+0.5y samples, these results fully revealed the composition-dependent photoluminescence properties of ZnxAgyInS1.5+x+0.5y nanocrystals. The relative quantum yield reached 35%. The fluorescence lifetimes (τ1=115–148 ns and τ2=455–483 ns) were analogous to those of AgInS2 and (AgIn)xZn2(1−x)S2. [ABSTRACT FROM AUTHOR]