Abstract
The heterogeneous electron transfer kinetics (k0 values), mass transport and thermodynamic properties (E0 values) associated with the FeIII/II process have been determined in aqueous solutions containing 0.1 M HCl, HClO4, bis(trifluoromethanesulfonyl)imide (HNTf2) or 0.05 M silicotungstic acid (H4[α-SiW12O40]) supporting electrolytes. The diffusion coefficient (D) values for FeIII and FeII are dependent on the radius of the electrolyte anion and follow the order D(SiW12O40 4−) < D(NTf2 −) < D(ClO4 −) < D(Cl−). The k0 values are found to be smaller at boron doped diamond (BDD) electrodes than glassy carbon (GC) electrodes, and influenced by the ion-pairing between electrolyte anions and FeIII and FeII. Based on the formal potential value, HNTf2 is found to be a more innocent electrolyte than commonly used HClO4 with regard to determine the true k0 values of the outer-sphere [Fe(H2O)6]3+/2+ process. Fourier transformed large amplitude alternating current voltammetry, which provides favorable signal to background ratio, was used to determine k0 values associated with the FeIII/II process in H4[α-SiW12O40] and HNTf2 electrolyte media at GC electrodes and probe the implications of the heterogeneity of the BDD electrode surface on the electrode kinetic determination in H4[α-SiW12O40] electrolyte media.
| Original language | English |
|---|---|
| Pages (from-to) | 421-430 |
| Number of pages | 10 |
| Journal | Electrochimica Acta |
| Volume | 249 |
| DOIs | |
| Publication status | Published - 20 Sep 2017 |
Keywords
- electrode heterogeneity
- electron transfer kinetics
- Fe process
- Fourier transformed alternating current voltammetry
- medium effect
Cite this
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A Systematic Study of the Mass Transport, Kinetic and Thermodynamic Properties of the FeIII/II Process at Glassy Carbon and Boron-Doped Diamond Electrodes. / Lin, Mingyue; Li, Jiezhen; Pan, Dawei; Bond, Alan M; Zhang, Jie.
In: Electrochimica Acta, Vol. 249, 20.09.2017, p. 421-430.Research output: Contribution to journal › Article › Research › peer-review
TY - JOUR
T1 - A Systematic Study of the Mass Transport, Kinetic and Thermodynamic Properties of the FeIII/II Process at Glassy Carbon and Boron-Doped Diamond Electrodes
AU - Lin, Mingyue
AU - Li, Jiezhen
AU - Pan, Dawei
AU - Bond, Alan M
AU - Zhang, Jie
PY - 2017/9/20
Y1 - 2017/9/20
N2 - The heterogeneous electron transfer kinetics (k0 values), mass transport and thermodynamic properties (E0 values) associated with the FeIII/II process have been determined in aqueous solutions containing 0.1 M HCl, HClO4, bis(trifluoromethanesulfonyl)imide (HNTf2) or 0.05 M silicotungstic acid (H4[α-SiW12O40]) supporting electrolytes. The diffusion coefficient (D) values for FeIII and FeII are dependent on the radius of the electrolyte anion and follow the order D(SiW12O40 4−) < D(NTf2 −) < D(ClO4 −) < D(Cl−). The k0 values are found to be smaller at boron doped diamond (BDD) electrodes than glassy carbon (GC) electrodes, and influenced by the ion-pairing between electrolyte anions and FeIII and FeII. Based on the formal potential value, HNTf2 is found to be a more innocent electrolyte than commonly used HClO4 with regard to determine the true k0 values of the outer-sphere [Fe(H2O)6]3+/2+ process. Fourier transformed large amplitude alternating current voltammetry, which provides favorable signal to background ratio, was used to determine k0 values associated with the FeIII/II process in H4[α-SiW12O40] and HNTf2 electrolyte media at GC electrodes and probe the implications of the heterogeneity of the BDD electrode surface on the electrode kinetic determination in H4[α-SiW12O40] electrolyte media.
AB - The heterogeneous electron transfer kinetics (k0 values), mass transport and thermodynamic properties (E0 values) associated with the FeIII/II process have been determined in aqueous solutions containing 0.1 M HCl, HClO4, bis(trifluoromethanesulfonyl)imide (HNTf2) or 0.05 M silicotungstic acid (H4[α-SiW12O40]) supporting electrolytes. The diffusion coefficient (D) values for FeIII and FeII are dependent on the radius of the electrolyte anion and follow the order D(SiW12O40 4−) < D(NTf2 −) < D(ClO4 −) < D(Cl−). The k0 values are found to be smaller at boron doped diamond (BDD) electrodes than glassy carbon (GC) electrodes, and influenced by the ion-pairing between electrolyte anions and FeIII and FeII. Based on the formal potential value, HNTf2 is found to be a more innocent electrolyte than commonly used HClO4 with regard to determine the true k0 values of the outer-sphere [Fe(H2O)6]3+/2+ process. Fourier transformed large amplitude alternating current voltammetry, which provides favorable signal to background ratio, was used to determine k0 values associated with the FeIII/II process in H4[α-SiW12O40] and HNTf2 electrolyte media at GC electrodes and probe the implications of the heterogeneity of the BDD electrode surface on the electrode kinetic determination in H4[α-SiW12O40] electrolyte media.
KW - electrode heterogeneity
KW - electron transfer kinetics
KW - Fe process
KW - Fourier transformed alternating current voltammetry
KW - medium effect
UR - http://www.scopus.com/inward/record.url?scp=85028442880&partnerID=8YFLogxK
U2 - 10.1016/j.electacta.2017.07.155
DO - 10.1016/j.electacta.2017.07.155
M3 - Article
VL - 249
SP - 421
EP - 430
JO - Electrochimica Acta
JF - Electrochimica Acta
SN - 0013-4686
ER -