Boosting Tetracycline Degradation with an S-Scheme Heterojunction of N-Doped Carbon Quantum Dots-Decorated TiO<sub>2</sub>


Karaca M., Eroglu Z., AÇIŞLI Ö., Metin O., KARACA S.

ACS OMEGA, vol.8, no.29, pp.26597-26609, 2023 (SCI-Expanded, Scopus) identifier identifier identifier

  • Publication Type: Article / Article
  • Volume: 8 Issue: 29
  • Publication Date: 2023
  • Doi Number: 10.1021/acsomega.3c03532
  • Journal Name: ACS OMEGA
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Directory of Open Access Journals
  • Page Numbers: pp.26597-26609
  • Kocaeli University Affiliated: Yes

Abstract

N-doped carbon quantum dots (N-CQDs) derived from the Rumex crispus L. plant were incorporated into TiO2 via a facile hydrothermal method. Asprepared materials were characterized and used in the photocatalytic tetracycline (TC) degradation under UVA light irradiation by examining several operational parameters involving the N-CQDs amount, initial TC concentration, pH, and photocatalytic reaction time. XRD analysis revealed the conversion of the rutile phase to the anatase phase after the incorporation of N-CQDs into the TiO2 structure. The results revealed that the N-CQDs/TiO2 photocatalysts demonstrated the highest efficiency in TC degradation compared to other processes of adsorption, photolysis (UVA), and photocatalysis with TiO2 (TiO2/UVA). Under optimized conditions, 10 mg/L TC at pH 5.15 with 0.2 g/L N-CQDs/TiO2 catalyst showed 97.7% photocatalytic degradation for 120 min under UVA irradiation. The formation of an S-scheme heterojunction between N-CQDs and TiO2 provided enhanced charge separation and strong redox capability, causing significant improvement in the photocatalytic performance of N-CQDs/TiO2. Trapping experiments showed that O-2(-) and h(+) are the predominant reactive species for the TC elimination in an aqueous solution.