Focusing on the interfacial charge transfer by carbon quantum dots from FeTiO3 perovskite for enhanced photocatalytic antibiotic degradation

Abstract

Herein, FeTiO3 perovskite particles were functionalized with carbon quantum dots (CQDs) using ultrasonication followed by impregnation methods. The functionalization enhanced visible light-driven degradation of cipro-floxacin (CIP) antibiotic via extended light absorption, promoted separation rate of photogenerated carrier and increased oxygen vacancies. The FeTiO3/CQDs composite including 20 mL of CQDs degraded 68.4 % of CIP within 120 min whereas FeTiO3 itself only degraded CIP by 36.5 %. On the basis of the structural character-ization, the successful introduction of CQDs was confirmed in the FeTiO3/CQDs composite. The increased ratio of oxygen species was proved by XPS and ESR measurements, and the improved charge transfer was supported by PL analysis. The degradation mechanism was identified via scavenger tests; super oxide radicals and holes were found dominant in the degradation reaction. Furthermore, the photocatalytic performance was boosted by adding two Fenton reagents to the reaction environment. The FeTiO3/CQDs composite catalyst also exhibited an excellent reusability and stability features. Accordingly, this study presented a novel and low-cost hybrid semiconductor as efficient and sustainable material for environmental purification under visible light irradiation.