[Studies on the anion recognition of N-aryl-N'-(4-ethyloxybenzoyl) thioureas derivatives by spectroscopy].

The interactions of N-aryl-N'-(4-ethyloxybenzoyl) thioureas derivatives and anions such as F-, Cl-, Br-, I-, CH3COO-, H2POT4-, HSO4- and NO3- in DMSO were investigated by UV-Vis and 1H NMR spectroscopy. The results showed that hydrogen--bonding complexes were formed between receptors and the three anions such as F-, CH3COO- and H2PO4-, and the solutions turned light yellow from colorlessness, but there had no evident binding with Cl-, Br-, I-, HSO4- and NO3-. It was regular that the two receptors had different binding ability with F-, CH3COO- and H2PO4-. For the same anion, the association constants followed the trend: receptor 1a > receptor 1b. The UV-Vis data indicated that a 1 : 1 stoichiometry complex was formed.

[UV spectroscopic characterization of the inclusion interaction of beta-cyclodextrin and sym-diphenyl-thiourea and sym-diphenyl-urea].

The inclusion interaction of beta-cyclodextrin and sym-diphenyl-thiourea and sym-diphenyl-urea was studied by UV spectra. The stoichiometry ratio for the formation of the inclusion complexes was determined by Hildebrand-Benesi equation linear analysis and molar ratio method. The standard molar Gibbs energies, enthalpies, and entropies were derived for the inclusion process by Ks at different temperatrues. The result showed that the host:guest ratio of inclusion complex between the two diphenyl compounds and beta-CD is 2 : 1, the stability constant (Ks) of 2 : 1 inclusion complexes was higher than that of 1 : 1 inclusion complexes due to cooperative binding in the close two hydrophobic cyclodextrin cavities, and the association of the guest molecule with beta-CD was favored by enthalpy changes, proving that the Van der Waals interaction and the dipole-dipole interaction were main binding forces of cyclodextrin inclusion complex.

Spectroscopic investigations on the simulated solar light induced photodegradation of 4-nitrophenol by using three novel copper(II) porphyrin-TiO2 photocatalysts.

Three porphyrins containing different functional groups (-OH, C-O2C2H5, -COOH), 5-(4-hydroxy) phenyl-10,15,20-triphenyl porphyrin (1a), 5-(4-ethylacetatatomethoxy) phenyl-10,15,20-triphenyl porphyrin (1b), 5-(4-carboxylatomethoxy) phenyl-10,15,20-triphenyl porphyrin (1c), were synthesized and characterized spectroscopically. The CuPp(2a, 2b, 2c)-TiO2 photocatalysts were then prepared and characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), UV-vis diffuse reflectance spectroscopy (UV-vis-DRS), Fourier-transform infrared spectroscopy (FT-IR). The photocatalytic activities of the photocatalysts were investigated by carrying out the photodegradation of 4-nitrophenol in aqueous solution under simulated solar irradiation. It was found that the CuPp(2a, 2b, 2c)-TiO2 enhanced the photocatalytic efficiency of bare TiO2 in photodegrading the 4-NP due to the interaction between CuPp(2a, 2b, 2c) and TiO2, resulted in the enhancement of the photogenerated electron-hole separation. The reasons of this enhanced photocatalytic activity were also discussed. Based on the present study, it could be considered as a promising photocatalyst for the further industrial application.