Electrochemical synthesis of some thiosemicarbazide derivatives doped polypyrrole electrodes and supercapacitor applications

Abstract

Thiosemicarbazide derivatives (TSC, N-Phenyl TSC, N-Cyclohexyl TSC) doped polypyrrole (PPy) based electrodes were synthesized in one step electropolymerization method. It was determined that thiosemicarbazide derivatives had an effect on the morphological and chemical structure of PPy. Among the thiosemicarbazide derivatives, it was determined that the additive of PPy that had the highest and most curative effect on the electrochemical energy storage performance was determined to be N-Cyclohexyl TSC, and its effects on the electrochemical performance at different concentrations were investigated. The PPy/N-Cyclohexyl TSC (2.5 mM) electrode exhibited a capacitance of 300.5 F/g at a potential operating range of 1.1 V, in 0.5 M H2SO4 electrolyte, and the current density of 0.5 A/g. The symmetrical supercapacitor device obtained using PPy/N-Cyclohexyl TSC (2.5 mM) electrode showed capacitance retention rate of 90.4% and 81.5% in 0.5 M H2SO4 and 1.0 M Na2SO4 electrolytes and at the end of the 5000 cycles life cycle test, respectively. In addition, the PPy/N-Cyclohexyl TSC (2.5 mM)/ PPy/N-Cyclohexyl TSC (2.5 mM) symmetrical supercapacitor device exhibits a specific capacitance of 175 F/g at a current density of 0.4 A/g in 0.5 M H2SO4, while 137.3 F/g in 1.0 M Na2SO4 electrolyte. The energy and power density values obtained at 0.5 M H2SO4 and 1.0 M Na2SO4 for the supercapacitor device were 8.7 Wh/kg, 343.4 W/kg and 19.1 Wh/kg, 883.5 W/kg, respectively.