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

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.