Details

Autor(en) / Beteiligte

• Li, Jiezhen
• Guo, Si-Xuan
• Bentley, Cameron L.
• Bano, Kiran
• Bond, Alan M.
• Zhang, Jie
• Ueda, Tadaharu

Titel

Electrode Material Dependence of the Electron Transfer Kinetics Associated with the [SVW11O40]3−/4− (VV/IV) and [SVW11O40]4−/5− (WVI/V) Processes in Dimethylformamide

Ist Teil von

• Electrochimica acta, 2016-05, Vol.201, p.45-56

Ort / Verlag

Elsevier Ltd

Erscheinungsjahr

2016

Link zum Volltext

Quelle

Elsevier ScienceDirect Journals Complete

Beschreibungen/Notizen

• [Display omitted] •The electrode kinetics (k0) of the [SVW11O40]3−/4−/5− processes have been determined.•The k0 values are electromaterial dependent.•Electromaterial dependent k0is not solely governed by the density of states.•The k0 values show a significant electrolyte concentration dependence. In this study, large amplitude Fourier transformed alternating current (FTAC) voltammetry has been used to determine the heterogeneous electron-transfer kinetics (k° and α values) associated with the vanadium [SVW11O40]3−/4− (VV/IV, E°=0.050V vs. Fc/Fc+, where Fc=ferrocene) and tungsten [SVW11O40]4−/5− (WVI/V, E°=−1.530V vs. Fc/Fc+) processes in dimethylformamide containing tetrabutylammonium hexafluorophosphate as the supporting electrolyte. At glassy carbon (GC), platinum (Pt), gold (Au) and boron-doped diamond (BDD), the VV/IV process is kinetically more facile than the WVI/V one. Excellent simulation-experiment fits were achieved for the VV/IV process at all electrode materials, and at a supporting electrolyte concentration of 0.1M, the k° value associated with this process increases in the order BDD<Pt≈Au<GC. By contrast, at all electrode materials except GC, generally poor simulation-experiment fits were achieved for the WVI/V process, preventing the data from being analysed quantitatively by FTAC voltammetry. Changing the concentration of supporting electrolyte from 0.1 to 0.5M has a significant influence on the kinetics, with the k° value increasing at GC and decreasing at Pt, Au and BDD. Overall, the findings indicate that differences in density of states do not fully explain the electrode material dependence of the k° values and that other factors such as surface functional groups (on GC) and the double layer effect need to be taken into consideration.