Unveiling the electrochemical excellence of sulfur and nitrogen-enriched 3D porous carbon nanofibers in high-performance energy storage devices

Recent research has faced challenges in achieving high specific capacitance and cycle stability with carbon nanofibers (CNFs) as supercapacitor electrodes. This study employs calcination/activation techniques to modify the electrochemical and structural properties of electrospun sulfur/nitrogen (S, N)-enriched CNFs. Combining the electrospinning process with these methods produces CNFs with a high energy density, enhancing non-faradaic processes. The 3D interconnected morphology of S, N-enriched CNFs possesses an appropriate surface area of 104.1 m²/g at 77 K with the high porous nature. Due to the excellent synergistic effect of nitrogen and sulfur atoms, the as-prepared porous CNFs showed excellent electrochemical performance in a three-electrode assembly. Under a neutral medium, the symmetric two-electrode cell displayed an outstanding electrochemical performance with a specific capacitance of 186F/g, an energy density of 25.8 Wh kg⁻¹, a power density of 500 W kg⁻¹ and excellent capacitance retention of 88.2 % over 3000 charge–discharge cycles. The findings strongly indicate that the as-prepared CNFs have the potential to advance significantly energy storage technology, surpassing other reported carbon materials.