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Abstract: The preparation of titania (TiO2), germania (GeO2) and binary TiO2–GeO2 oxide with different Ti/Ge ratio gels based on sol–gel method with surfactant-assisted mechanism and their application for dye-sensitized solar cells (DSCs) were reported. The samples were calcined and characterized by nitrogen adsorption porosimetry, X-ray diffraction (XRD) and morphology was investigated by field emission scanning electron microscopy (FE-SEM). The XRD results suggested that germanium substituted for titanium in the TiO2 lattice because of the gradual shift of 101 diffraction peak of anatase type of TiO2. The higher surface area from binary oxides samples was due to the added oxide acting as a crystal growth inhibiter. For the application for DSCs, the electrodes fabricated from binary oxides sample gave significant higher J sc when compared to cell that fabricated by sample TiO2 electrode. The consequence effects of added germanium were analyzed and discussed. [Copyright &y& Elsevier]

The triplet state of zinc non-peripheral substituted alkylbenzopyridoporphyrazines and position isomers were measured, using laser-flash photolysis in poly(methyl methacrylate) film. The triplet lifetime increased with an increasing pyridine number in the molecule. The lowest symmetric isomer having two pyridine rings in the molecule showed the longest triplet state lifetime. The compound was suitable for the use the photosensitizer as a photodynamic therapy of cancer. [Copyright &y& Elsevier]

• A new class of salicylideneanilines that show exclusive photochromism was prepared. • The photobleaching process under various temperatures was precisely analyzed. • A new kinetic model provided a distinct classification of photobleaching behavior. Three types of Schiff bases of anilines were derived from a salicylaldehyde bearing super bulky substituents, the dinuclear zinc complex [Zn 2 (bpsal)(CH 3 CO 2) 2 ](BF 4) 2 (Hbpsal = 3,5-bis(N , N -bis(2-pyridylmethyl)aminomethyl)-2,4-dihydroxybenzaldehyde). These Schiff bases formed isomorphous crystal structures, which exhibited almost similar photochromism and no detectable thermochromism. Single-crystal microscopic UV–vis absorption spectroscopy was performed to track the time course of the photoproduct at various temperatures between −75 and 135 °C. The decay curves were characterized by two parameters, k 1 and k 2 , which contribute to linear and quadratic terms, respectively, in terms of the extent of reaction. The effects of temperature and visible-light intensity on the parameters were discussed. The analyzed data were compared to another series of Schiff bases with moderately bulky substituents derived from 3,5-di(tert -butyl)salicylaldehyde. The results suggested that the crystal packing is much more important than the electronic substituent effects in determining the photochromic properties. [ABSTRACT FROM AUTHOR]