Poly(1,5-diaminonaphthalene) films for supercapacitor electrode materials: effect of electropolymerization technique on specific capacitance

Poly(1,5-diaminonaphthalane) (1,5-PDAN) films have been successfully synthesized on pencil graphite electrode (PGE) from aqueous solution of 0.1 M monomer and 1.0 M perchloric acid (HClO₄) by different electrochemical techniques which are cyclic voltammetry (CV) and chronoamperometry (CA). The field emission scanning electron microscopy has been used to analyze the surface morphologies of 1,5-PDAN-coated PGE by CV (PGE/1,5-PDAN(CV)) and CA (PGE/1,5-PDAN(CA)). Electrochemical measurements have been performed to evaluate usability of the electrodes for supercapacitors using CV, electrochemical impedance spectroscopy (EIS), galvanostatic charge–discharge and repeating chronopotentiometry (RCP) methods in 1.0 M HClO₄. When compared the results of electrochemical measurements, it is concluded that PGE/1,5-PDAN(CA) has higher specific capacitance than PGE/1,5-PDAN(CV). Despite having high specific capacitance, long-term charge–discharge cycling stability of PGE/1,5-PDAN(CA) is lower than that of PGE/1,5-PDAN(CV). Additionally, electrodes exhibit high power and energy density, according to galvanostatic charge–discharge measurements. In conclusion, it can be said that PGE/1,5-PDAN(CV) and PGE/1,5-PDAN(CA) are promising materials for supercapacitor applications.