Synthesis and plasma treatment of nitrogen-doped graphene fibers for high-performance supercapacitors

Graphene fiber-based supercapacitor has aroused great interest as a flexible power source in future wearable electronics. However, the low electrochemical performance of graphene fibers (GFs) usually causes the serious limitation of use in practical applications due to the material stacking, hydrophobicity and fabrication process complexity. In this work, a facile and effective plasma-assisted strategy is put forward to increase specific surface area, tune hierarchically porous structure and promote wettability of nitrogen-doped graphene fibers (NGFs), resulting in the improvement of electrochemical performance. The supercapacitor assembled from plasmatreated NGFs shows superior capacitance (878 mF/cm2 at 0.1 mA/cm2 current density) and high energy density (19.5 mu W h/cm2 at 40 mW/cm2 power density), which is 23.7% and 131.4% higher than that of NGFs and GFs, respectively. Additionally, the fiber-based supercapacitor based on plasma-treated NGFs exhibits high rate capability of 59.8% and excellent cyclic performance (95.8% retention over 10,000 cycles). These plasma-treated NGFs can be promising candidates for high-performance and flexible power sources in future wearable electronics.

Automated summary

This study introduces a plasma-assisted treatment strategy to enhance the electrochemical performance of nitrogen-doped graphene fibers, resulting in a significant improvement of the supercapacitor's performance. The plasma treatment increases the specific surface area, tunes hierarchically porous structure, and improves wettability of the NGFs, leading to higher capacitance and energy density. The plasma-treated NGFs exhibit superior rate capability and cyclic performance, making them promising candidates for high-performance and flexible power sources in future wearable electronics.