Perchlorate Interchange during the Redox Process of PPy/PVS Films in an Acetonitrile Medium. A Voltammetric and EDX Study

Citations Over TimeTop 16% of 2004 papers

Abstract

Polypyrrole/poly(vinyl sulfonate) (PPy/PVS) films in acetonitrile containing 0.1 M LiClO4 were studied by cyclic voltammetry. Consecutive voltammograms pointed to a continuous increase in the charge involved in the process, suggesting a rise in the number of the electroactive participants involved in the redox process. However, voltammograms obtained for the PPy/ClO4 films in analogous conditions pointed to a steady-state behavior from the very early cycles. Theoretical studies based on the Nernst and Butler-Volmer equations indicated that perchlorate ions are involved during the oxidation/reduction process of the PPy/PVS films when the steady state is reached. This result was confirmed by "ex situ" energy-dispersive X-ray analysis of the films. In this regard, the electrochemical behavior of PPy/PVS polymers was similar to that of PPy/ClO4 films when a high number of cycles were carried out. The exchange of ClO4- during the redox reaction of the PPy/PVS films made it necessary to incorporate Li+ cations inside the polymer during the initial voltammetric cycles to compensate for the negative charges of PVS polyanions. Li+ cations are mainly stabilized inside the polymer by the ion pairs formed with the sulfonated groups of the PVS. An increase and shift of the voltammetric cycles indicated a restructuring of the polymeric chains with consecutive scans.

Related Papers

• → Perchlorate : environmental occurrence, interactions, and treatment(2006)141 cited
• → On the Ligating Properties of Sulfonate and Perchlorate Anions Towards Zinc(1997)39 cited
• → Fundamentals of electrochemistry(II)——Thermodynamic equilibrium and Nernst equation(2013)2 cited
• → Two innovative derivation methods of the Nernst equation without any additional assumptions(2023)1 cited
• → Rederivation of Nernst's equation without any additional assumptions(2023)