Dielectric barrier discharge plasma-assisted modification of g-C3N4/Ag2O/TiO2-NRs composite enhanced photoelectrocatalytic activity

J Environ Sci (China). 2021 Jun:104:113-127. doi: 10.1016/j.jes.2020.11.029. Epub 2020 Dec 18.

Abstract

Dielectric barrier discharge (DBD) plasma applied as surface treatment technology was employed for the modification of Ag2O and graphitic carbon nitride (g-C3N4) powders. Subsequently, the pretreated powders were sequentially loaded onto TiO2 nanorods (TiO2-NRs) via electro-deposition, followed by calcination at N2 atmosphere. The results indicated that at the optimal plasma discharge time of 5 min for modification of g-C3N4 and Ag2O, photocurrent density of ternary composite was 6 times to bare TiO2-NRs under UV-visible light irradiation. Phenol was degraded by using DBD plasma-modified g-C3N4/Ag2O/TiO2-NRs electrode to analyze the photoelectrocatalytic performance. The removal rate of phenol for g-C3N4-5/Ag2O-5/TiO2-NRs electrode was about 3.07 times to that for TiO2-NRs electrode. During active species scavengers' analysis, superoxide radicals and hydroxyl radicals were the main oxidation active species for pollutants degradation. A possible electron-hole separation and transfer mechanism of ternary composite with high photoelectrocatalytic performance was proposed.

Keywords: Degradation mechanism; Photoelectrochemical catalysis; Plasma treatment; Ternary material; Z-scheme structure.

MeSH terms

  • Catalysis
  • Nanotubes*
  • Silver*
  • Titanium

Substances

  • titanium dioxide
  • Silver
  • Titanium