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The Cu 2 O@H 2 Ti 3 O 7 nanocomposite was prepared through a facile hydrothermal method. The as-prepared samples were investigated by powder X-ray di®raction (XRD), high resolution transmission electron microscopy (HRTEM), laser Raman spectroscopy (LRS), N 2 adsorptiondesorption measurements and UV-Vis di®use re°ection spectroscopy (UV-Vis-DRS). The photocatalytic performance of the as-prepared Cu 2 O@H 2 Ti 3 O 7 nanocomposite is evaluated by the oxidation of ethyl mercaptan (EM) under sunlight irradiation. The results indicate that the Cu 2 O nanoparticles are integrated uniformly on H 2 Ti 3 O 7 nanotubes, and the absorption edge of the nanocomposite has obviously shifted to visible light region compared to H 2 Ti 3 O 7 nanotubes. There is an obvious synergistic e®ect existing between the dispersed Cu 2 O nanoparticles and H 2 Ti 3 O 7 nanotubes, and the Cu 2 O@H 2 Ti 3 O 7 composite shows stronger visible spectral response and wider absorbance. Then, an enchanced photodegradation activity is obtained for the removal of EM under sunlight irradiation compared to its precursors.

Assays for carbendazim (Car) with high sensitivity and on-site screening have been urgently required to protect the ecosystem and prevent disease. In this work, a simple, sensitive, and reliable sensing system based on photoinduced electron transfer was established to detect carbendazim utilizing ultrathin graphitic carbon nitride (g-C3N4) nanosheets and rhodamine B (RB). Carbendazim reacts with g-C3N4 by electrostatic interactions to form π–π stacking, and the quenching of the blue fluorescence is caused by electron transfer. While RB works as a reference fluorescence sensor without any fluorescence change, leading to obvious ratiometric fluorescence variation from blue to purple. Under optimal conditions, a favorable linear range from 20 to 180 nM was obtained, with a low detection limit of 5.89 nM. In addition, a portable smartphone sensing platform was successfully used for carbendazim detection in real samples with excellent anti-interference capability, demonstrating the potential applications of carbendazim monitoring.

To explore the structure of chiral ligands important in asymmetric catalysis, the density functional theory has been applied to study the ground‐state geometries and isomerization processes of 2‐amino‐2′‐hydroxy‐1,1′‐binaphthyl. The study shows that there are four isomers for 2‐amino‐2′‐hydroxy‐1,1′‐binaphthyl, each of which has R‐ and S‐ enantiomer. The isomerization between R‐conformations is easier than the racemization between R‐ and S‐ enantiomer. A parallel reaction mechanism via anti‐enantiomerization routes was proposed for the racemization of 2‐amino‐2′‐hydroxy‐1,1′‐binaphthyl, which provides a valuable reference for the design, synthesis, and resolution of chiral ligands.