Novel Ag3PO4/ZnWO4-modified graphite felt electrode for photoelectrocatalytic removal of harmful algae: Performance and mechanism

J Hazard Mater. 2024 May 15:470:134198. doi: 10.1016/j.jhazmat.2024.134198. Epub 2024 Apr 3.

Abstract

A novel Ag3PO4/ZnWO4-modified graphite felt electrode (AZW@GF) was prepared by drop coating method and applied to photoelectrocatalytic removal of harmful algae. Results showed that approximately 99.21% of chlorophyll a and 91.57% of Microcystin-LR (MCLR) were degraded by the AZW@GF-Pt photoelectrocatalytic system under the optimal operating conditions with a rate constant of 0.02617 min-1 and 0.01416 min-1, respectively. The calculated synergistic coefficient of photoelectrocatalytic algal removal and MC-LR degradation by the AZW@GF-Pt system was both larger than 1.9. In addition, the experiments of quenching experiments and electron spin resonance (ESR) revealed that the photoelectrocatalytic reaction mainly generated •OH and •O2- for algal removal and MC-LR degradation. Furthermore, the potential pathway for photoelectrocatalytic degradation of MC-LR was proposed. Finally, the photoelectrocatalytic cycle algae removal experiments were carried out on AZW@GF electrode, which was found to maintain the algae removal efficiency at about 91% after three cycles of use, indicating that the photoelectrocatalysis of AZW@GF electrode is an effective emergency algae removal technology.

Keywords: Graphite felt electrode; Harmful algae; Inactivation mechanism; Photoelectrocatalysis.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Catalysis
  • Chlorophyll / chemistry
  • Chlorophyll A / chemistry
  • Electrochemical Techniques
  • Electrodes*
  • Graphite* / chemistry
  • Graphite* / radiation effects
  • Harmful Algal Bloom
  • Marine Toxins*
  • Microcystins* / chemistry
  • Microcystins* / isolation & purification
  • Oxides / chemistry
  • Phosphates / chemistry
  • Photochemical Processes
  • Silver Compounds* / chemistry
  • Tungsten / chemistry
  • Water Purification / methods
  • Zinc / chemistry

Substances

  • Graphite
  • Microcystins
  • Silver Compounds
  • cyanoginosin LR
  • silver phosphate
  • Marine Toxins
  • Phosphates
  • Oxides
  • Tungsten
  • Chlorophyll A
  • Zinc
  • Chlorophyll