Doping induced enhanced photocatalytic performance of SnO2:Bi3+ quantum dots toward organic pollutants

Bismuth (Bi)-doped tin oxide (SnO2) quantum dots were synthesized via a one-step hydrothermal method. The as-prepared samples were characterized with various techniques. Photocatalytic activity of the as-synthesized photocatalysts were evaluated through photocatalytic degradation of Rhodamine B (RhB) and Ciprofloxacin hydrochloride (CIP) solution under simulated sunlight irradiation. Results showed that the Bi-doped SnO2 quantum dots had enhanced photocatalytic performance than the pure counterpart, where the photocatalytic efficiencies of 5Bi- SnO2 toward RhB and CIP were ca. 1.75 and 1.53-fold higher than that of pure SnO2 (56.02 % and 58.11 %). The outstanding photodegradation efficiency of the obtained composites were due to enhanced absorbance of light as well as the effective separation and migration of photo-generated carriers. The mineralization rate of CIP reached 57.40 % after 90 min photocatalytic decomposition with 5Bi-SnO2. Meanwhile, the antibacterial activity of CIP toward Escherichia coli DH5a had been largely eliminated after 5Bi-SnO2 treatment. This work may increase the feasibility of purifying the environmental wastewater with a high efficiency and stable photocatalyst.