Вид документа : Статья из журнала Шифр издания : Автор(ы) : Dorosheva I. B., Valeeva A. A., Rempel A. A., Trestsova M. A., Utepova I. A., Chupakhin O. N. Заглавие : Synthesis and physicochemical properties of nanostructured TiO2 with enhanced photocatalytic activity Место публикации : Inorganic Materials. - 2021. - Vol. 57, № 5. - С. 503-510 Предметные рубрики: ХИМИЧЕСКИЕ НАУКИ Ключевые слова (''Своб.индексиров.''): titanium dioxide--sol–gel method--photocatalysis Аннотация: Nanostructured titanium dioxide (TiO2) with a crystallite size from 10 to 85 nm, photocatalytically active for organic reactions under illumination with visible light, has been prepared by a sol–gel process using a titanium tetrabutoxide solution in ethanol with an initial pH of 6. According to X-ray diffraction characterization results, the as-prepared titanium dioxide was amorphous. Annealing in a hydrogen atmosphere for 1 h at 400°C led to the formation of an anatase phase, and annealing in the temperature range from 600 to 800°C resulted in the anatase–rutile phase transition. The crystallite size of titanium dioxide increased from 10 to 75 nm as the annealing temperature was raised from 400 to 1000°C (furnace annealing for 1 h) and from 60 to 85 nm as the annealing time at a temperature of 800°C was increased from 30 to 240 min. Diffuse reflection spectra showed that the band gap of TiO2 decreased from 3.3 to 2.6 eV as the annealing temperature was raised from 200 to 1000°C. The specific surface area data obtained by BET measurements showed that the samples annealed at the highest temperature (1000°C) had the smallest surface area, which dropped from 307 to 1m2/g. The efficiency of the synthesized TiO2 tested as a catalyst for oxidative S H N cross-coupling of acridine with indole demonstrated an in crease in product yield from 35 to 80% as the annealing temperature was raised to 800°C. Varying the 800°C annealing time from 30 to 180 min had no effect on the reaction product yield, which ranged from 70 to 80%. Доп.точки доступа: Dorosheva, I. B.; Valeeva, A. A.; Rempel, A. A.; Trestsova, M. A.; Utepova, I. A.; Chupakhin, O. N.