Prospective ultrathin layered Fe2O3 doped reduced graphene oxide, polythiophene, and carbon black hybrid nanostructures for high performance supercapacitors

In this study, a ternary nanocomposite of rGO/Fe2O3/PTh was synthesized within a blended polymer matrix. The materials were extensively characterized by spectral (FTIR-ATR, EDX), morphological (SEM, AFM), thermal (TGA-DTA), particle size (BET) and electrical conductivity (Four-point probe and admittance plots from EIS) analyses. Hybrid electrodes for supercapacitor devices were subsequently fabricated. Cyclic voltammetry (CV), galvanostatic charge-discharge (GCD), and electrochemical impedance spectroscopy (EIS) were employed to investigate the electrochemical performance. The rGO/Fe2O3/PTh/CB electrode exhibited the highest specific capacitances of 1057.24 F/g at 2 mV/s (CV), 169.46 F/g at 0.1 A/g (GCD), and 43.8 F/g (EIS). In addition, areal and volumetric capacitances of CA=42.36 F/cm2 and CV= 3530.37 F/cm3, respectively, were achieved at 0.1 A/g. The rGO/Fe2O3/PTh electrodes also showed a high specific capacitance of 743.88 F/g at 2 mV/s and excellent electrochemical stability, retaining 90.63% of their capacitance after 1000 cycles at 100 mV/s. Overall, the rGO/Fe2O3/PTh/CB hybrid electrode represents a simple and cost-effective candidate for supercapacitor applications. Most importantly, the fabricated device demonstrated superior specific capacitance and cyclic stability compared to several previously reported Fe2O3-based symmetric supercapacitors. Furthermore, the equivalent circuit model RS(C1(R1(R2C2))) was applied to evaluate the correlation between theoretical and experimental EIS data.