Electrochemical study of the Fe(CN)4−6/Fe(CN)3−6 couple at the ITO/NaCl interface

✍ Scribed by L. Tamisier; A. Caprani

• Publisher: Elsevier Science
• Year: 1987
• Tongue: English
• Weight: 451 KB
• Volume: 32
• Category: Article
• ISSN: 0013-4686
• DOI: 10.1016/0013-4686(87)85068-5

✦ Synopsis

The electrochemical behaviour of the Fe(CN):-/Fe(CNa-redox couple at the tin-doped'indium oxide (ITO)/NaCI 0.154 M interface was investigated using a rotating disc electrode. The study of the relationship between the stationary current and the rotation speed I (Q exhibits a law of the I -' = In!+,, + Id -t type, where Id, proportional to Sl ' 's, is identical to the Levich value for an uniformly accessible disc. The electrochemical impedance reveals three time constants. The additional time constant can be attributed either to a non-electrochemical step in series with the electron transfer step, or to a topographical relaxation of a partly blocked interface. The kinetic parameters of the electron transfer step were determined according to the charge transfer resistance and to In_,.

Their values were found to be equal to 0.37 and 0.35 mA .cm * for the transfer coefficient and the exchange current density, respectively.