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Carbon nitride/bismuth sulfide (C3N4/Bi2S3) nanocomposites were prepared by a facile one‐step in situ calcination method using ammonium thiocyanate and bismuth chloride as reagents. The crystal structure, composition, and morphology of the nanocomposites were characterized by X‐ray diffraction (XRD), Fourier transform infrared (FT‐IR) spectroscopy, scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The photocatalytic degradation of rhodamine B (RhB) was carried out to evaluate the photocatalytic activity of the nanocomposites under visible light irradiation. The as‐prepared C3N4/Bi2S3 nanocomposites displayed enhanced visible light absorption. These photocatalysts exhibited superior photodegradation performance under visible light irradiation compared to pure C3N4. Meanwhile, the C3N4/Bi2S3 nanocomposites exhibited remarkably stable photocatalytic efficiency after five cycles of photodegradation of RhB. The C3N4/Bi2S3 heterostructure improved the separation and transfer efficiency of the photogenerated electron–hole pairs. It played an important role for the enhanced photocatalytic performance of the nanocomposite photocatalysts. [ABSTRACT FROM AUTHOR]

A novel fluorescent probe CN3, containing 1,8‐naphthalimide and picolinate units, was synthesized, and its structure was characterized by 1H nuclear magnetic resonance spectroscopy (H NMR), 13C nuclear magnetic resonance spectroscopy (C NMR), and mass spectroscopy techniques. The detection property of CN3 toward copper ions (Cu2+) has been investigated in ethanol–HEPES buffer (v/v = 1/1, pH = 7.40) solution by UV–Vis absorption and fluorescence emission spectra. The results showed that CN3 had a highly selective and sensitive fluorescence quenching response to Cu2+, which was attributed to the generation of weak fluorescent N‐ethyl‐4‐hydroxyphenyl‐1,8‐ naphthalimide (compound 2) in polar ethanol–HEPES buffer (v/v = 1/1, pH = 7.40) via selective hydrolysis reaction. The detection of CN3 for Cu2+ was not influenced in the presence of other competing metal ions, and the limit of detection was as low as 50.0 nM. Therefore, the color of CN3 changed from colorless to yellowish when the Cu2+ was added. Furthermore, the fluorescent probe CN3 was utilized to detect Cu2+ in real water samples with fine performance. [ABSTRACT FROM AUTHOR]

A novel coumarin derivative CTT was synthesized via the condensation of 7‐(N,N‐diethylamino) coumarin‐3‐aldehyde with 5‐amino‐1,3,4‐thiadiazole‐2‐thiol and its structure was characterized using infrared spectroscopy (IR), 1H NMR, mass spectrometry (MS) techniques, and elemental analysis. The recognition properties of CTT with metal ions were investigated in CH3CN–H2O (v/v = 1/1) solution using UV–vis absorption and fluorescence emission spectrum method. The results showed that CTT could monitor Cu2+ and Hg2+ simultaneously as a dual‐function chemosensor in CH3CN–H2O (v/v = 1/1). CTT could be used to detect Cu2+ colorimetrically; when using CTT, a color change from yellowish‐brown to yellowish‐green could be readily observed by the naked eye. CTT showed turn‐on fluorescent recognition of Hg2+, the fluorescence enhancement was attributed to the inhibited C=N isomerization and the obstructed excited state intramolecular proton transfer (ESIPT) of CTT. The recognition mechanism of CTT for Cu2+ and Hg2+ was studied by experiments and theoretical calculations, respectively. Therefore, CTT has the ability to be a "single chemosensor for dual targets." [ABSTRACT FROM AUTHOR]

A novel Cr3+‐selective ratiometric fluorescent chemosensor 1‐substitued‐2‐carbazoleylbenzoimidazole (L) based on benzimidazole and carbazole was synthesized and characterized by nuclear magnetic resonance (1H/13C NMR), Fourier transform infrared spectrometry (FTIR), and mass spectroscopy. L could selectively detect Cr3+ over other metal ions by UV–vis absorption and fluorescence emission spectroscopic methods in CH3CN. L showed ratiometric fluorescent recognition of Cr3+; the fluorescent responses could be observed by naked eye under a UV lamp. The binding stoichiometry ratio of the L–Cr3+ complex was found to be 1:1 according to Job’s plot and MALDI‐TOF MS analysis. The results of DFT calculation supported this conclusion. [ABSTRACT FROM AUTHOR]

Rod-like ZnO nanoparticles ( NPs) were synthesized from zinc powder by a simple hydrothermal oxidation method. The presence of acetylacetone could promote the oxidation reaction of Zn and the formation of hexagonal nanorods. Then, the as-prepared samples were annealed in N2 , O2 , and air atmosphere at 550°C for 2 h to control the number of oxygen vacancies in the samples. The samples were characterized by X-ray diffraction, scanning electron microscopy, X-ray photoelectron spectroscopy, and UV-vis spectroscopy. The correlation between the oxygen vacancies and the photocatalytic activity was investigated. The results reveal that the annealing process alters the samples' bandgap and number of the oxygen vacancies, thereby improving the photocatalytic activity. The enhancement of photodegradation efficiency arising from the appropriate content of oxygen vacancies is discussed. [ABSTRACT FROM AUTHOR]