Enhanced heterogeneous activation of peroxydisulfate by S, N co-doped graphene via controlling S, N functionalization for the catalytic decolorization of dyes in water

Chemosphere. 2018 Nov:210:120-128. doi: 10.1016/j.chemosphere.2018.07.011. Epub 2018 Jul 3.

Abstract

3D porous sulfur and nitrogen co-doped graphene aerogel has been fabricated by a facile one-pot process. Both experimental and theoretical studies have demonstrated that sulfur and nitrogen co-doping could synergistically enhance the catalytic performance for activating peroxydisulfate (PDS) compared to the original and N doped graphene aerogels. The ratio of sulfur/nitrogen in the aerogel can be controlled by regulating the additions of thiourea and urea sources, and the aerogel with the S/N ratio of about 1:2.5 shows a better catalytic effect due to more significant changes in the electrostatic potential and the surface charge distribution, as revealed by the theoretical simulations. The radical quenching tests indicated that both SO4·- and ·OH radicals could be formed in the SN-rGO aerogel + PDS system and contribute most to RhB degradation.

Keywords: Activation mechanism; Heterogeneous activation; RhB decolorization; Sulfur and nitrogen co-doping.

MeSH terms

  • Catalysis
  • Color
  • Coloring Agents / chemistry*
  • Graphite / chemistry*
  • Nitrogen / chemistry
  • Sulfur / chemistry
  • Water Pollutants, Chemical / chemistry*

Substances

  • Coloring Agents
  • Water Pollutants, Chemical
  • Sulfur
  • Graphite
  • Nitrogen