Fotokatalytická redukce oxidu uhličitého v přítomnosti fotokatalyzátorů na bázi TiO2

Abstract

This bachelor thesis deals with the photocatalytic reduction of carbon dioxide in the presence of titanium dioxide-based photocatalysts. TiO2-based photocatalysts were prepared by hydrothermal method (HT-TiO2) and sol-gel method (SG-TiO2). These photocatalysts were characterized by X-ray diffraction spectrometry (XRD), X-ray photoelectron spectroscopy (XPS), field emission scanning electron microscopy (FE-SEM) and diffuse reflectance spectrometry (DRS). The photocatalytic reduction of CO2 was realized in a stainless-steel batch reactor using a UV Hg lamp with a wavelength of 254 nm for an irradiation period of 8 h. Gas phase samples were analyzed on a gas chromatograph with a BID detector. The efficiencies of the prepared photocatalysts were compared with the commercial photocatalyst P25 and showed higher efficiency in the formation of the all products, which were H2, CO and CH4. The SG-TiO2 photocatalyst prepared by sol-gel method showed the highest efficiency. A key role was played by the amount of OH- groups on the surface of the photocatalysts.