Electropolymerization of pyrrole from a deep eutectic solvent for supercapacitor applications

Abstract

In this study, polypyrrole was electroplated onto graphite surface electrochemically from a urea and choline chloride mixture of deep eutectic solvent as the deposition solution. SEM, Raman and FTIR analysis showed that pyrrole was electrochemically polymerized homogeneously as the polypyrrole (PPy) on the graphite surface. Surface morphology of PPy/graphite composite electrode synthesized from the deep eutectic solvent electrolyte medium resembled blistered structures. Electroplated PPy-based composite electrodes were transferred to water containing LiClO4, acetonitrile containing LiClO4 and pure Reline deep eutectic solvent electrolytes to examine their electrochemical properties in different electrolytes. PPy displayed capacitance behavior in all these cycling electrolytes. PPy/graphite composite electrode was reached to 535 F g−1 in aqueous and organic electrolyte. Rate limiting reaction of PPy modified electrodes in three different electrolyte baths is between surface and diffusional controlled mechanism. Electropolymerization of pyrrole from deep eutectic solvent electrolyte media was electrochemically active in three different electrolyte media and is a promising material for supercapacitor applications.