Understanding persulfate production at boron doped diamond film anodes

Research output: Contribution to journalArticle

69 Citations (Scopus)

Abstract

This research used molecular modeling and rotating disk electrode experiments (RDE) to investigate possible reaction pathways for persulfate production via electrolysis of sulfuric acid solutions using boron doped diamond (BDD) film anodes. Density functional theory (DFT) modeling indicated that uncatalyzed oxidation of SO42- and HSO4-occurs at lower potentials than water oxidation, and that sulfate radical species (SO4-• and HSO4) may be produced via direct electron transfer, or via reaction with hydroxyl radicals. The RDE experiments indicated that rates of persulfate generation were strongly dependent of the condition of the electrode surface, and that aged electrode surfaces favored water oxidation over direct SO42 and HSO4- oxidation. Combination of sulfate radical species in solution is the lowest energy pathway for persulfate production. Sulfate radical species may also react with radical sites on the electrode surface and produce chemisorbed intermediates that can stabilize sulfate radical species. Reaction of the chemisorbed intermediates with a bisulfate radical can produce persulfate via a surface catalyzed pathway. However, the activation barriers for this pathway are much higher than those for persulfate production via solution phase species.

Original languageEnglish (US)
Pages (from-to)68-74
Number of pages7
JournalElectrochimica Acta
Volume150
DOIs
StatePublished - Dec 20 2014

Fingerprint

Boron
Diamond films
Anodes
Electrodes
Oxidation
Rotating disks
Molecular modeling
Experiments
Surface waters
Sulfuric acid
Electrolysis
Hydroxyl Radical
Density functional theory
Chemical activation
sulfate radical
Sulfates
Electrons
Water

Keywords

  • Anode
  • BDD
  • Boron doped diamond
  • Electrosynthesis
  • Persulfate

ASJC Scopus subject areas

  • Electrochemistry
  • Chemical Engineering(all)

Cite this

Understanding persulfate production at boron doped diamond film anodes. / Davis, Jake; Baygents, James C; Farrell, James.

In: Electrochimica Acta, Vol. 150, 20.12.2014, p. 68-74.

Research output: Contribution to journalArticle

@article{07a6b1b587324939aec1ae666c7d0f5f,
title = "Understanding persulfate production at boron doped diamond film anodes",
abstract = "This research used molecular modeling and rotating disk electrode experiments (RDE) to investigate possible reaction pathways for persulfate production via electrolysis of sulfuric acid solutions using boron doped diamond (BDD) film anodes. Density functional theory (DFT) modeling indicated that uncatalyzed oxidation of SO42- and HSO4-occurs at lower potentials than water oxidation, and that sulfate radical species (SO4-• and HSO4•) may be produced via direct electron transfer, or via reaction with hydroxyl radicals. The RDE experiments indicated that rates of persulfate generation were strongly dependent of the condition of the electrode surface, and that aged electrode surfaces favored water oxidation over direct SO42 and HSO4- oxidation. Combination of sulfate radical species in solution is the lowest energy pathway for persulfate production. Sulfate radical species may also react with radical sites on the electrode surface and produce chemisorbed intermediates that can stabilize sulfate radical species. Reaction of the chemisorbed intermediates with a bisulfate radical can produce persulfate via a surface catalyzed pathway. However, the activation barriers for this pathway are much higher than those for persulfate production via solution phase species.",
keywords = "Anode, BDD, Boron doped diamond, Electrosynthesis, Persulfate",
author = "Jake Davis and Baygents, {James C} and James Farrell",
year = "2014",
month = "12",
day = "20",
doi = "10.1016/j.electacta.2014.10.104",
language = "English (US)",
volume = "150",
pages = "68--74",
journal = "Electrochimica Acta",
issn = "0013-4686",
publisher = "Elsevier Limited",

}

TY - JOUR

T1 - Understanding persulfate production at boron doped diamond film anodes

AU - Davis, Jake

AU - Baygents, James C

AU - Farrell, James

PY - 2014/12/20

Y1 - 2014/12/20

N2 - This research used molecular modeling and rotating disk electrode experiments (RDE) to investigate possible reaction pathways for persulfate production via electrolysis of sulfuric acid solutions using boron doped diamond (BDD) film anodes. Density functional theory (DFT) modeling indicated that uncatalyzed oxidation of SO42- and HSO4-occurs at lower potentials than water oxidation, and that sulfate radical species (SO4-• and HSO4•) may be produced via direct electron transfer, or via reaction with hydroxyl radicals. The RDE experiments indicated that rates of persulfate generation were strongly dependent of the condition of the electrode surface, and that aged electrode surfaces favored water oxidation over direct SO42 and HSO4- oxidation. Combination of sulfate radical species in solution is the lowest energy pathway for persulfate production. Sulfate radical species may also react with radical sites on the electrode surface and produce chemisorbed intermediates that can stabilize sulfate radical species. Reaction of the chemisorbed intermediates with a bisulfate radical can produce persulfate via a surface catalyzed pathway. However, the activation barriers for this pathway are much higher than those for persulfate production via solution phase species.

AB - This research used molecular modeling and rotating disk electrode experiments (RDE) to investigate possible reaction pathways for persulfate production via electrolysis of sulfuric acid solutions using boron doped diamond (BDD) film anodes. Density functional theory (DFT) modeling indicated that uncatalyzed oxidation of SO42- and HSO4-occurs at lower potentials than water oxidation, and that sulfate radical species (SO4-• and HSO4•) may be produced via direct electron transfer, or via reaction with hydroxyl radicals. The RDE experiments indicated that rates of persulfate generation were strongly dependent of the condition of the electrode surface, and that aged electrode surfaces favored water oxidation over direct SO42 and HSO4- oxidation. Combination of sulfate radical species in solution is the lowest energy pathway for persulfate production. Sulfate radical species may also react with radical sites on the electrode surface and produce chemisorbed intermediates that can stabilize sulfate radical species. Reaction of the chemisorbed intermediates with a bisulfate radical can produce persulfate via a surface catalyzed pathway. However, the activation barriers for this pathway are much higher than those for persulfate production via solution phase species.

KW - Anode

KW - BDD

KW - Boron doped diamond

KW - Electrosynthesis

KW - Persulfate

UR - http://www.scopus.com/inward/record.url?scp=84909584443&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84909584443&partnerID=8YFLogxK

U2 - 10.1016/j.electacta.2014.10.104

DO - 10.1016/j.electacta.2014.10.104

M3 - Article

AN - SCOPUS:84909584443

VL - 150

SP - 68

EP - 74

JO - Electrochimica Acta

JF - Electrochimica Acta

SN - 0013-4686

ER -