An Application of Conducting Polymer Polypyrrole for the Design of Electrochromic pH and CO2Sensors

In this research, conducting polymer – polypyrrole (Ppy), was electrochemically polymerized on the indium tin oxide coated glass (glass/ITO) electrode. The adhesion of Ppy on the surface of ITO was improved by modification with triethoxymethylsilane (TEMS). Potential cycling was applied for electrochemical deposition of Ppy layer and cyclic voltammograms were recorded during the deposition to monitor polymerization process. Cyclic voltammetry and the potential pulse sequence (PPS)-based chronoamperometry methods complemented the registration of absorbance spectra of glass/ITO(TEMS)/Ppy at various pH and different concentrations of CO2. The applicability of glass/ITO(TEMS)/Ppy electrode in the design of electrochromic sensor sensitive toward CO2 has been evaluated. Cyclic voltammetry based experiments at different potential sweep rates in presence and absence of CO2 were performed in order to evaluate charge transfer phenomenon in glass/ITO(TEMS)/Ppy structure.