Photocatalytic Activity of P25-TiO2 Modified with Yttrium Oxide Towards Ciprofloxacin

The article considers the effect of modification of commercial material P25-TiO2 with yttrium oxide and the effect of the modifier nature on the photocatalytic activity towards ciprofloxacin. TiO2 modification with yttrium oxide enhances the degree of antibiotic degradation. Increase in modifier content affects the photoactivity of TiO2 ambiguously: when yttrium chloride is used as a precursor, photoactivity increases; when yttrium nitrate is used – photoactivity decreases. Additional use of an oxidant (H2O2) significantly increases (more than 2 times) efficiency of the photocatalytic process. It has been found that at low concentrations of antibiotic aqueous solution (up to $10\ \mathrm{mg/dm^{3}}$), its photodegradation over TiO2 modified with yttrium oxide reaches 100%. However, in case of high concentrations of ciprofloxacin (up to $50\ \mathrm{mg/dm^{3}}$), complete degradation of the antibiotic is observed only when the combination of TiO2 modified with yttrium oxide and oxidant H2O2 is utilized in the photocatalytic process.