Herein, polypyridine (P25Py) is for the first time evaluated as an anode material for organic matter based electric energy storage devices. P25Py is synthesized both chemically and electrochemically and the influence of electrolyte and solvent on the doping behavior of the material is investigated in propylene carbonate and acetonitrile with LiClO4 and TBAPF6. A battery consisting of P25Py coupled to a lithium metal disc is assembled and the electrochemical performance and cycling stability of the conjugated polymer is analyzed. In all electrolyte combinations P25Py is conductive and shows reversible redox chemistry between -1.0 and -2.0 V vs ferrocene with capacitive response characteristics. The electrochemical impedance spectroscopy response of the material can be described by a Randles equivalent circuit with a finite length Warburg diffusion element in which the diffusion coefficient of the cations increases with increasing doping level of the polymer. In the battery cell configuration the polymer shows reversible cycling with no capacity fading during the first 100 cycles without conducting additives. P25Py thus provides a promising alternative conducting polymer base for electrical energy storage applications which expands both the potential widow as well as the electrolyte compatibility of the flora of known conducting polymers.
ASJC Scopus subject areas
- Physical and Theoretical Chemistry
- Electronic, Optical and Magnetic Materials
- Surfaces, Coatings and Films