New electrodes based on composites of polyphenothiazine with carbon nanomaterials

Abstract

The goal of this research is to obtain new electrode hybrid coatings for electrochemical devices applications. Nanocomposites based on unsubstituted polyphenothiazine (PPTA) and carbon nanomaterials (CNM) were prepared for the first time. Reduced graphene oxide (RGO), single-walled and multi-walled carbon nanotubes (SWCNT and MWCNT) were used as CNM. Hybrid nanocomposites were prepared by two methods: via oxidative polymerization of PTA in the presence of CNM (CNM/PPTA-1), or from pre-synthesized polymer solution in DMF containing CNM followed by solvent removal (CNM/PPTA-2). The structure and morphology of PPTA-derived nanocomposites were studied by means of FTIR spectroscopy, X-ray diffraction, and FE-SEM. The nanocomposite composition dependence of conductivity was demonstrated. Electrochemical behavior of the electrode coatings prepared on the basis of the said polymer and CNM/PPTA nanocomposites thereof was studied by CV methods. All the samples were found to be electroactive in 1 M sulfuric acid. An addition of carbon nanomaterials was shown to improve reversibility of the electrode processes that is related to formation of nanocarbon conductive framework in the composite with a highly developed surface filled with thin layers of the polymer. CNM/PPTA nanocomposites exhibit the electrocatalytic effect to the redox behavior of ferro/ferricyanide couple in 1 M H2SO4.