FCNTs@CoS2 composite for supercapacitor applications: electrochemical measurements and theoretical calculations

Abstract

This study presents an evaluation of the FCNTs@CoS₂ composite for supercapacitor applications through a comprehensive analysis involving theoretical computations and electrochemical measurements (cycle voltammetry, or CV, and galvanostatic charge-discharge, or GSCD). The structural characteristics and morphology of the synthesized FCNTs@CoS₂ composites were examined using X-ray diffraction (XRD), scanning electron microscopy (SEM), Brunauer–Emmett–Teller (BET) analysis, and X-ray photoelectron spectroscopy (XPS). The performance of the composite is compared to pure CoS₂, revealing a substantial improvement in specific capacitance. At 1 A g⁻¹, the specific capacitances of CoS₂ and FCNTs@CoS₂ electrodes are measured at 197 F g⁻¹ and 493 F g⁻¹, respectively, highlighting the superior performance of the composite. Furthermore, the FCNTs@CoS₂ electrode demonstrates exceptional stability, retaining 91.2% of its capacity after 4000 cycles, in contrast to the CoS₂ electrode's 64.9% retention after 3000 cycles. These results underscore the remarkable potential of the FCNTs@_CoS2 composite as a high-performance and long-lasting material for supercapacitor electrodes, promising advancements in energy storage technology.