A novel S-scheme heterojunction of Cd0.5Zn0.5S/BiOCl with oxygen defects for antibiotic norfloxacin photodegradation: Performance, mechanism, and intermediates toxicity evaluation

J Colloid Interface Sci. 2023 Jan;629(Pt A):276-286. doi: 10.1016/j.jcis.2022.08.136. Epub 2022 Aug 25.

Abstract

S-scheme heterojunction structure can endow the photocatalysts with high-performance photo-degradation of pharmaceuticals and personal care products (PPCPs) since it can remain the photogenerated electrons/holes with stronger redox ability. Herein, an integrative S-scheme heterojunction photocatalyst building from Cd0.5Zn0.5S nanoparticles and BiOCl microflowers with oxygen vacancies (OVs) was developed. Moreover, the in-situ grown process ensures the firm contact and intense electron coupling between BiOCl and Cd0.5Zn0.5S. As a result, Cd0.5Zn0.5S/BiOCl exhibited a significant reinforcement of photo-activity and stability for the abatement of antibiotic norfloxacin, manifesting a 2.8-fold or 9.6-fold enhancement compared to pristine Cd0.5Zn0.5S or BiOCl. Cd0.5Zn0.5S/BiOCl also shows good resistance to alkaline, sodium salts and humic acid. The performance of Cd0.5Zn0.5S/BiOCl to photocatalytically degrade other PPCPs with different molecular structures was further confirmed. At last, the ability of Cd0.5Zn0.5S/BiOCl for PPCPs de-toxicity was verified by evaluating the toxicity of norfloxacin and its degradation intermediate. This study demonstrates a new S-scheme heterojunction photocatalyt for efficient removal of PPCPs as well as provides some insights into developing high-performance metal sulfide solid-solution-based S-scheme heterojunctions for water decontamination.

Keywords: Antibiotic degradation; Cd(0.5)Zn(0.5)S/BiOCl; Oxygen vacancy; S-scheme; Toxicity analysis; Visible-light photocatalysis.

MeSH terms

  • Anti-Bacterial Agents / chemistry
  • Anti-Bacterial Agents / pharmacology
  • Cadmium*
  • Catalysis
  • Humic Substances
  • Light
  • Norfloxacin*
  • Oxygen
  • Pharmaceutical Preparations
  • Photolysis
  • Salts
  • Sodium
  • Sulfides
  • Water
  • Zinc

Substances

  • Norfloxacin
  • Cadmium
  • Anti-Bacterial Agents
  • Oxygen
  • Humic Substances
  • Salts
  • Zinc
  • Sulfides
  • Water
  • Pharmaceutical Preparations
  • Sodium