Binary-phase TiO2 modified Bi2MoO6 crystal for effective removal of antibiotics under visible light illumination

A series of binary-phase TiO₂ modified Bi₂MoO₆ nanocrystals have been prepared via a solvothermal-calcination process. Trace TiO₂ modification can effectively enhance the visible light catalytic activity of Bi₂MoO₆ to remove the antibiotics in aqueous solution. The obtained TiO₂/Bi₂MoO₆ composites were investigated by some physicochemical techniques like XRD, N₂ adsorption, SEM, TEM, UV–vis DRS, Raman, XPS, PL and Photo-electrochemical measurement. The presence of TiO₂ nanoparticles (NPs) influenced the crystal growth of Bi₂MoO₆, decreasing the crystal size of Bi₂MoO₆ and effectively promoting its specific surface area. Moreover, the conduction band of TiO₂ can serve as the electron transfer platform, which largely boosts the effective separation of photocarriers at TiO₂/Bi₂MoO₆ heterojunction interface. With optimal TiO₂ content (0.41 wt%), TiO₂/Bi₂MoO₆ exhibited the best photocatalytic performance for different antibiotics degradation, e.g. ciprofloxacin, tetracycline and oxytetracyline hydrochloride under visible light irradiation. Moreover, the mechanism for enhanced photocatalytic performance in ciprofloxacin degradation was illuminated.