Photocatalytic Degradation of Tetracycline Hydrochloride in Aqueous Solution at Ambient Conditions Stimulated by Gold Containing Zinc- Titanium Oxide Films

Abstract

AbstractIncorporation of gold species in the matrix of titania and zinc-containing titania films was applied for an improvement of their photocatalytic capability in the tetracycline hydrochloride (TC) destruction. Two different procedures of the gold metal generation by photo-thermo-reduction method were tested in this process. Multi-layered coatings of these films enhanced the rate of TC degradation as well as had effect on the reaction products. Reproducibility of the film activity was observed after several irradiation procedures without any additional treatment of the catalyst. Surface plasmon resonance band of gold nanoparticles was obviously shifted to the blue region in UV-vis absorption spectrum as a result of light action supposing the gold oxidation to ionic species. The plasmon band completely reverted to the original one upon exposure to air in the dark. Matrix-assisted laser desorption/ionization measurements confirmed the destruction of the cyclic structure of the antibiotics molecule.