FeS2/SRGO nanocomposite: Synthesis, characterization and comprehensive study of supercapacitor behavior in different electrolytes

Abstract

In this study, fine FeS2 nanoparticles were synthesized using novel, easy and efficient methods. Graphene oxide was reduced and sulfur-doped in one step by a new simple chemical method and used to prepare the (pyrite- sulfur doped reduced graphene oxide) FeS2-SRGO nanocomposite. The prepared samples were characterized and approved by using Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), field emission scanning- electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX) mapping, transmission electron microscopy (TEM), cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) methods. The FeS2-SRGO nanocomposite was coated on a carbon paste electrode substrate and the electrochemical capacitive behavior of the electrode was studied by CV and galvanostatic charge-discharge (GCD) method in different electrolytes including 6 M KOH, 1 M H2SO4, 1 M Na2SO4, 1 M NaCl, 1 M NaNO3, 1 M KCl, 3 M NaOH. Experimental results and specific capacitance calculations showed that the electrode in 1 M H2SO4 electrolyte with a specific capacity of 277 F g−1 has the best supercapacitor performance. The capacity retention is about 90 % of the initial capacity even after 200 charge and discharge cycles.