Electrochemical properties of novel porous carbon based material synthesized from polycyclic aromatic hydrocarbons

Polycyclic aromatic hydrocarbons (PAHs) are interesting compounds from both fundamental and applied research points of view, because these molecules can be considered as well-defined cut-outs of graphene. Starting from relatively small PAHs it is possible to electrochemically synthesize in one easy step electroactive films consisting of larger PAH molecules. In the present work benzo(a)pyrene was used as the monomer and by potential cycling in propylene carbonate, porous films were obtained consisting of PAH molecules with an average number of carbon atoms in the range 40-60, evidenced by Raman and infrared spectroscopy. Electrochemical activity during oxidation of the resulting amorphous poly(benzopyrene) (PBP) films was determined in propylene carbonate and acetonitrile by in situ conductance measurements and electrochemical impedance spectroscopy. Additionally, based on impedance spectra a new equivalent circuit was proposed which accurately describes the electrochemical properties of the synthesized PBP films. The model was verified by comparing calculated conductivity values with experimental values obtained from in situ conductance measurements. It was found that PBP films exhibit fast ion transport with electrical conductivity of ∼6.6 mS cm−1. The results presented in this work imply that PBP is an interesting material for electrochemical applications.