Deposição de dióxido de estanho-flúor (SnO2:F) em substrato transparente para uso em células fotoeletroquímicas

Abstract

The conductor glasses have been used as transparent conductor oxides (TCO’s). Due to its transmittance in the visible spectrum and low sheet resistance, TCO’s have been employed as a constituent component of photoeletrochemical cells activated with dye. This work is dedicated to the conductor glass fabrication, at a lab scale, on 2,6 cm x 7,6 cm glass substrates by spray pyrolyris method and application of the conductor glasses in photoeletrochemical cells of the type Grätzel and immense electrode. The work involve the fabrication of the conductor glasses, deposition of the silver-doped titanium oxide (TiO2:Ag) films on conductor glasses, preparation of the electrolyte, choice and preparation of the dye and then to close and to characterize of the cells by open circuit voltage (Voc) and short circuit current (Icc). The conductor glass is of the type fluorine-doped tin oxide (SnO2:F). The deposition of SnO2:F layer is make on the glass substrate with temperature of 600ºC from precursor solution. The heat source is ceramic heater of flat surface in a stove. The spray gun is used for to deposit the precursor solution on glass substrate. The conductor glasses and electrodes of SnO2:F/TiO2:Ag are characterized by measures of x-ray diffraction (XRD), scanning electron micrograph (SEM), UV-vis, electric resistance and Möhr strong. The average transmittance of the conductor glass 70 % in the wavelength regions of 650 nm – 800 nm. The average reflectance of 20 % in the electrodes SnO2:F/TiO2:Ag with extract of spinach in the wavelength regions of 650 nm – 700 nm. In the characterization of the cells, measures of Voc and Icc are obtained for cells under illumination. To hotoeletrochemical cell of the type Grätzel with extract of spinach the measures are Voc = 0,264 V and Icc = 1,4 μA; while that for the photoeletrochemical cell of the type Grätzel with methylene blue the measures are Voc = 0,186 V and Icc = 3,5 μA.