Hierarchically Porous Nitrogen-Doped Carbon Nanowires Derived from Polypyrrole Nanowires for Supercapacitors and Lithium–Sulfur Batteries

Nanostructured porous carbon materials have a series of excellent properties, which have attracted much attention in the field of energy storage. In this study, we have effectively synthesized porous nitrogen-doped carbons of distinct shapes (spherical particles and elongated nanowires) by subjecting polypyrrole particles and nanowires to steam activation. Especially, the combination of high surface area, good electrical conductivity, and nitrogen doping allows carbon nanowires to deliver excellent electrochemical performance in both supercapacitors and lithium–sulfur batteries. Drawing from their captivating characteristics, the hierarchically porous nitrogen-doped carbon nanowires (NCNW), which originate from polypyrrole nanowires and serve as electrodes for supercapacitors, have displayed remarkable electrochemical attributes in an organic electrolyte. These attributes encompass a substantial specific capacitance and commendable rate response. Furthermore, NCNW, when utilized as a medium for sulfur, demonstrates noteworthy electrochemical behavior, notably in terms of elevated discharge capacities (reaching 1033 mA h g–1 at a rate of 0.1 C) and excellent cycling performance (maintaining 690 mA h g–1 over 200 cycles at a rate of 0.5 C).