Achievement of Near-Reversible Behavior for the [Fe(CN)6]3-/4- Redox Couple Using Cyclic Voltammetry at Glassy Carbon, Gold, and Platinum Macrodisk Electrodes in the Absence of Added Supporting Electrolyte

Autor: Melissa Bunin Rooney, Alan M. Bond, Darren C. Coomber
Rok vydání: 2000
Předmět:
Zdroj: Analytical Chemistry. 72:3486-3491
ISSN: 1520-6882
0003-2700
DOI: 10.1021/ac991464m
Popis: Voltammetric studies in the absence of added supporting electrolyte are presently dominated by the use of near-steady-state microelectrode techniques and millimolar or lower depolarizer concentrations. However, with this methodology, large departures from conventional migration−diffusion theory have been reported for the [Fe(CN)6]3-/4- process at both carbon fiber and platinum microdisk electrodes. In contrast, data obtained in the present study reveal that use of the transient cyclic voltammetric technique at glassy carbon, gold, or platinum macrodisk electrodes and K4[Fe(CN)6] or K3[Fe(CN)6] concentrations of 50 mM or greater provides an approximately reversible response in the absence of added electrolyte. It is suggested that the use of very high [Fe(CN)6]3- and [Fe(CN)6]4- concentrations overcomes problems associated with a diffuse double layer and that large electrode surface areas and faster potential sweep rates minimize electrode blockage and passivating phenomena that can plague voltammetric stu...
Databáze: OpenAIRE