One-step potentiostatic codeposition and electrochemical studies of poly(1-pyrenyl)-2,5-di(2-thienyl)pyrrole-co-pyrrole) film for electrochemical supercapacitors

Abstract

In this paper, we report a simple, low-cost, and environmentally friendly electrochemical method to obtain a novel copolymer consisting of l-pyrenyl-2,5-di(2-thienyl)pyrrole and pyrrole on a pencil graphite electrode (PGE). Poly(1-pyrenyl)-2,5-di(2-thienyl)pyrrole-co-pyrrole) that is P(PyrPy-co-Py) film was prepared by one-step potentiostatic codeposition in an ethanol solution containing PyrPy and Py monomers for supercapacitor applications. The electrodeposition of homopolymer and copolymer modified electrodes was carried out on the surface of the PGE via chronocoulometry. For comparison, P(Py)/PGE and P(PyrPy)/PGE were also electrochemically synthesized under the same reaction conditions. The surface morphologies of all the electrode materials were analyzed by field emission scanning electron microscopy. The capacitive properties of the modified PGEs were investigated in 1 M H2SO4 electrolyte solution by cyclic voltammetry, electrochemical impedance spectroscopy, and galvanostatic charge-discharge methods. Compared with P(Py)/PGE and P(PyrPy)/PGE, the P(PyrPy-co-Py)/PGE composite exhibited the best electrochemical behavior and had the highest specific capacitance value of 397. 18 F g(-1) in 1 M H-2 SO4 at a scan rate of 2 mV s(-1). These results indicated that this modified electrode can be used as an electrode material for electrochemical supercapacitors.