Sol-Gel TiO2 thin films sensitized with the mulberry pigment cyanidin

Abstract

TiO2 films have various applications, among them solar cells and photodegradation of pollutants. In this study, we investigated TiO2 films functionalized with the organic dye cyanidin extracted from black mulberry (Morus nigra). The TiO2 was functionalized by the sol-gel method and the film was deposited on glass substrates by dip-coating. Our aim was to investigate the interaction between the semiconductor and the dye, as well as the influence of the velocity and number of deposits on the characteristics of the film. Using ultraviolet-visible spectroscopy, we observed a shift from the maximum absorption band at 545 nm for the dye’s ethanol solution to 595 nm for the film, indicating interaction of the cyanidin with the TiO2. The absorption spectra in the infrared region of the functionalized TiO2 particles showed bands characteristic of the oxide and indicated their interaction with the dye. Using profilometry and m-line techniques, we found that the films presented thicknesses in the order of 100 nm. A SEM analysis confirmed the high density of the films

Effect of UV-light on the uniaxial tensile properties and structure of uncoated and TiO2 coated Bombyx mori silk fibers

“…The peak at 801 cm À1 is assigned to -TiO-Ti-stretching [28]. The bands observed at 1028, 1415, and 1527 cm À1 were attributed to stretching and vibrations of the Ti-O-Ti group [29]. The peaks at 2853 and 2924 cm À1 were attributed to the symmetrical and antisymmetrical C-H stretching vibration of CH 2 [30,31], respectively.…”

Vegetable-based dye-sensitized solar cells

“…[44][45][46] The TiO 2 nanoparticles diameter was found to affect considerably the photocurrent which decreases (from 0.28 to 0.13) with increasing nanoparticles sizes (from 5 nm to 18 nm). 343 A thermo-gravimetric and spectroscopic analysis on TiO 2 films functionalized with cyanidin from black mulberry through sol-gel method, 435 revealed that when linked to TiO 2 surface, cyanidins are stable for temperatures up to 400 1C. 46 A more systematic study was carried out by Zhang et al, 337 investigating the photosensitizing properties of more than 20 different natural dyes (such as vegetables, bacteria and insects) in DSSCs.…”

New synthesis strategies for effective functionalization of kaolinite and saponite with silylating agents

“…These materials have attracted considerable attention in the past years [1][2][3]. Zeolites, silica, and other matrices are being used as inorganic hosts to prepare hybrid nanocomposites [4][5][6][7][8][9][10]. These materials are extremely interesting because they combine the properties of their components in the interface, thus giving rise to composites with unique magnetic, photoluminescent, mechanical, optical, optoelectronic, conducting, and catalytic properties for specific applications in areas such as optoelectronics, catalysis, and biomaterials, among others [11][12][13][14].…”