Enhanced Degradation of Oxytetracycline Antibiotic Under Visible Light over Bi2WO6 Coupled with Carbon Quantum Dots Derived from Waste Biomass

Molecules. 2024 Dec 4;29(23):5725. doi: 10.3390/molecules29235725.

Abstract

Improving the photogenerated carrier separation efficiency of individual semiconductor materials has always been a key challenge in photocatalysis. In this study, we synthesized a novel photocatalytic material, N-CQDs/UBWO, in situ by combining nitrogen-doped carbon quantum dots (N-CQDs) derived from discarded corn stover with ultrathin Bi2WO6 nanosheets (UBWO). Detailed characterization indicates that the random distribution of N-CQDs on the UBWO surface increases the specific surface area of UBWO, which is beneficial for the adsorption and degradation of oxytetracycline (OTC). More importantly, N-CQDs act as electron acceptors, promoting the effective separation of photogenerated charges, prolonging the lifetime of charge carriers in UBWO, and thereby enhancing the degradation efficiency of OTC. As a result, the optimized 3wt%N-CQDs/UBWO could degrade 85% of OTC within 40 min under visible light, with a removal rate four times that of pure Bi2WO6. The performance of photocatalytic degradation over OTC by 3wt%N-CQDs/UBWO exceeds that of most reported Bi2WO6-based photocatalysts. The EPR analysis confirmed that ∙O2- and ∙OH are the main active species in the photocatalytic degradation of OTC on 3wt%N-CQDs/UBWO. This study provides insight into designing green, low-cost, and efficient photocatalysts using CQDs derived from waste biomass and the degradation of emerging pollutants like antibiotics.

Keywords: antibiotic contamination; carbon quantum dots; degradation mechanism; visible-light photocatalysis; waste biomass.

MeSH terms

  • Adsorption
  • Anti-Bacterial Agents* / chemistry
  • Biomass*
  • Bismuth* / chemistry
  • Carbon* / chemistry
  • Catalysis
  • Light*
  • Oxytetracycline* / chemistry
  • Photolysis
  • Quantum Dots* / chemistry
  • Tungsten Compounds* / chemistry

Substances

  • Oxytetracycline
  • Carbon
  • Bismuth
  • Anti-Bacterial Agents
  • Tungsten Compounds
  • bismuth wolframate

Grants and funding

This research was supported by the Xijing University Special Fund for High-Level Talents (No. XJ24B20).