Electrochemical thin film deposition of polypyrrole on different substrates

Polypyrrole is one of the important conductive polymers that are widely used in energy storage systems, biosensors and electronics. The electrochemical synthesis of polypyrrole has advantages of simple process, mass production and low cost. In this study, polypyrrole thin films were deposited on different electrode substrates by cyclovoltammetric (CV), galvanostatic and potentiostatic deposition methods. Results demonstrated that the galvanostatic deposition method could provide higher electrochemical activity for the films. Different electrode materials including gold, glassy carbon and ink-made carbon composite electrodes were investigated for polypyrrole deposition. The conductive films on all substrates exhibited p-type conjugate polymer characteristics. However, the substrate properties had great impact on the stability of the deposited thin film and some composite carbon substrate materials demonstrate the best performance. The mechanism of the instability of polypyrrole was suggested. The study also demonstrates the feasibility of using carbon ink to make composite electrodes for possible applications in energy storage systems and electrochemical sensors.