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To obtain optimal luminescence, 0.12 g of GdVO4:3%Eu3+ nanocrystals (NCs) and different volumes of nitrogen‐doped carbon dots (N‐CDs) crude solution were used as precursors, and the composite synthesized using the hydrothermal deposition method showed optimal luminescence when 11 ml (2.45 mmol) crude solution was used. In addition, similar composites with the same molar ratio as GVE/cCDs(11) were also prepared with the hydrothermal and physical mixing processes. Based on the test results of XRD, XPS, and PL spectra, for the composite GVE/cCDs(11), the highest (lowest) peak intensity of the C–C/C=C (C=O/C=N) bond, which was 1.18 (0.75) times that of GVE/cCDs‐m, indicated most N‐CDs deposition and led to their highest emission intensity under 365 nm excitation, although nitrogen atoms in the composite were shed slightly during the deposition process. Finally, as can be seen from the patterns designed for security applications that the optimally luminescent composite is one of the most promising candidates in the anti‐counterfeiting field. [ABSTRACT FROM AUTHOR]

Abstract: In this work, undoped YVO4 nanocrystals (10–15nm in size) were first synthesized by a solvothermal method, and they were ion exchanged for Eu3+ ions to form YVO4:Eu3+ nanocrystals, which were then used to prepare YVO4:Eu3+–thenoyltrifluoroacetone hybrid nanostructures. As expected, the ion exchanged YVO4:Eu3+ nanocrystals exhibited the characteristic V–O charge transfer excitation band. Much stronger luminescence has been observed in the YVO4:Eu3+–thenoyltrifluoroacetone hybrid nanostructures due to energy transfer from thenoyltrifluoroacetone ligands to Eu3+ ions. The dependence of luminescence of the YVO4:Eu3+–thenoyltrifluoroacetone hybrid nanostructures on the Eu3+ concentration and amount of thenoyltrifluoroacetone ligands was investigated in detail, and optimal preparation conditions were determined. Their UV–Vis absorption spectra and BET specific surface area were measured. X-ray diffraction technique, transmission electron microscopy, and Fourier transform infrared spectroscopy were used to study their microstructural characteristics. [Copyright &y& Elsevier]

A novel and convenient approach to the synthesis of polysubstituted isochromanones is described. Irradiation of 2-formyl phenylalkeno-derivatives with UV light in benzene solution afforded the corresponding products in up to 98% yield. The possible reaction mechanism is proposed and further supported by the isotopic experiments. [ABSTRACT FROM AUTHOR]

To obtain optimal luminescence, 0.12 g of GdVO 4 :3%Eu 3+ nanocrystals (NCs) and different volumes of nitrogen-doped carbon dots (N-CDs) crude solution were used as precursors, and the composite synthesized using the hydrothermal deposition method showed optimal luminescence when 11 ml (2.45 mmol) crude solution was used. In addition, similar composites with the same molar ratio as GVE/cCDs(11) were also prepared with the hydrothermal and physical mixing processes. Based on the test results of XRD, XPS, and PL spectra, for the composite GVE/cCDs(11), the highest (lowest) peak intensity of the C-C/C=C (C=O/C=N) bond, which was 1.18 (0.75) times that of GVE/cCDs-m, indicated most N-CDs deposition and led to their highest emission intensity under 365 nm excitation, although nitrogen atoms in the composite were shed slightly during the deposition process. Finally, as can be seen from the patterns designed for security applications that the optimally luminescent composite is one of the most promising candidates in the anti-counterfeiting field., (© 2023 John Wiley & Sons Ltd.)