Electrochemical behavior of composite electrode based on sulphonated polymeric surfactant (SPEEK/PSS) incorporated polypyrrole for supercapacitor

Abstract

Sulfonated polymeric surfactants integrated polypyrrole composites have been prepared and exploited as electrode material for supercapacitor application where sulfonated poly (ether ether ketone) SPEEK and poly (styrene sulfonate) PSS have been used as surfactant as well as dopant in polypyrrole (PPy). These composites are conveniently prepared via in-situ chemical oxidation polymerization of pyrrole using FeCl3 as oxidant at varying weight ratio of SPEEK/PSS and investigated through Fourier transforms infrared spectroscopy, Thermal gravimetric analysis/Derivative thermal gravimetric, Field emission scanning electron microscopy, and electrochemical performance. Field emission scanning electron micrographs divulge granular morphology of composite with spongy and baggy structure. Electrochemical performance of all the composites has been investigated through cyclic voltammetry (CV), galvanostatic charge discharge (GCD) and electrochemical impedance spectroscopy (EIS) measurements. Results reveal that electrochemical properties of composites significantly depend upon different feeding ratio of SPEEK or PSS due to the availability of sulfonating groups. After comparative study, high specific capacitance 330F/g of SP4 (PPy:SPEEK (w/w) 60:40) at scan rate of 2mV/s, that also correlates well with the GCD findings. High energy density obtained as 23.8Wh/kg of SP4 composite at power density of 1000W/kg demonstrates as new promising electrode material for supercapacitors.