Significantly activated persulfate by novel carbon quantum dots-modified N-BiOCl for complete degradation of bisphenol-A under visible light irradiation

• Published in: The Science of the total environment Vol. 870; p. 161804
• Main Authors: Zhang, Jianqiao, Li, Zhiyang, Lei, Qian, Zhong, Dan, Ke, YiXin, Liu, WenJie, Yang, Lei
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 20.04.2023
• Subjects: BiOCl; Carbon quantum dots; Nitrogen doped; Persulfate; Photocatalysis; Nitrogen doped; BiOCl; Carbon quantum dots; Photocatalysis; Persulfate
• ISSN: 0048-9697; 1879-1026
• DOI: 10.1016/j.scitotenv.2023.161804

The practical application of bismuth-based photocatalysts in the field of micropollutant photodegradation is limited due to their weak light absorption and rapid charge recombination. Herein, we have developed a novel carbon quantum dots-modified N-BiOCl (CDs-N-BiOCl) photocatalyst to activate persulfate (PS) for the complete elimination of endocrine-disruptor bisphenol A (BPA) under visible light irradiation. The photoelectric properties characterization shows that N atoms could replace Cl atoms or adsorb on Bi atoms to form local N 1s states in the BiOCl lattice, accompanied by the introduction of doping energy levels that shorten the electron migration distance. Meanwhile, the decorated CDs could effectively accept the photoinduced electrons from N-BiOCl conduction band to facilitate the charge separation. Thus, the 7%CDs-N-BiOCl (7CNB) nanocomposite synergistically activated PS realized rapid and effective degradation of BPA within 20 min (degradation efficiency and mineralization reached 100 % and 66.4 % respectively). Moreover, the 7CNB/PS system displayed favorable adaptability, durability, and interference resistance. Furthermore, the biotoxicity experiments demonstrated that the photodegradation intermediates promoted the growth of Escherichia coli which indicates its eco-friendliness for practical application. Finally, the electron transfer mechanism and the formation of reactive oxygen species in the photodegradation process were interpreted. In short, this work will present a promising strategy for bismuth-based photocatalysts to be used for the efficient treatment of real water bodies under visible light irradiation. [Display omitted] •CDs-N-BiOCl photocatalyst was fabricated by hydrothermal calcination.•The doping energy level introduced by N atoms shortens the electron hopping distance.•The decorated carbon dots act as electron acceptor to promote charge separation.•The CDs-N-BiOCl/persulfate(PS) system enhances the bisphenol A photodegradation.•The charge transfer mechanism is well explained and evaluated.