I'm working on the electrodeposition of Polypyrrole on stainless steel by chronoamperometry at a positive potential of 1.17V in a LiClO4/CH3CN medium. My question concerns the cathodic reactions of Pt counter-electrode??. I couldn't find any work on this subject.
the reduction reactions (cathode) Pt depend on the medium, in your case it can give the reduction of chlorates ClO4-.
After an extensive literature search, I've found the answer to this question and would like to publish it so that researchers in this field can better understand the subject:
Electrochemical polymerization of pyrrole in an organic medium involves the loss of one electron during anodic oxidation of the monomer and loss of two protons during the coupling [1-2]. As the solvent and electrolyte are stable in the study area [3,4], the only reaction that takes place at the Pt counter electrode (cathode in our case) is the release of hydrogen due to the reduction of protons released during pyrrole electropolymerisation according to the following equation:
2H+ + 2e- ---> H2
[1] : J. Heinze, Topics in Current Chemistry, Vol.152, Editeur E. Steckhan, Springer Verlag,Berlin (1990) p. 1. [2] : M.M. Gvozdenović, B.Z. Jugović, J.S. Stevanović, B.N. Grgur, Electrochemical synthesis of electroconducting polymers, Hemijska Industrija. 68 (2014) 673–684.
[3]: A. Tabchouche, A. Ourari, N. Zoubeidi, D. Zerrouki, Electrochemistry Preparation of Electrodes based on Polypyrrole and polymethylpyrrole/Manganese Dioxide Particles, Energy Procedia. 36 (2013) 1009–1017.
[4]: J. Zieja, J. Gadomska-Trzos, Z. Stojek, Electrooxidation and Electroreduction of Undiluted Acetonitrile at Platinum Microelectrodes. In Situ Determination of Water in Acetonitrile, Electroanalysis. 13 (2001) 621–625.