Effective approaches to co-dope lignin based concave shaped carbon nanofibers with multiple elements for...

Area of Science:

• Materials Science
• Electrochemistry
• Sustainable Energy

Background:

• Lignin valorization for sustainable materials is crucial.
• Lignin-based carbon nanofibers (LCNF) show promise for supercapacitors but suffer from performance limitations due to structural heterogeneity.
• Developing high-performance LCNF requires advanced fabrication and doping strategies.

Purpose of the Study:

• To synthesize flexible and porous LCNF simultaneously doped with nitrogen (N), sulfur (S), and zinc (Zn).
• To evaluate the electrochemical performance of these co-doped LCNF as electrode materials for supercapacitors.
• To demonstrate a sustainable and high-value utilization of lignin for advanced energy storage.

Main Methods:

• Electrostatic spinning of lignin precursor solutions.
• Controlled carbonization of electrospun fibers.
• Simultaneous doping with N, S, and Zn elements.
• Electrochemical characterization using three-electrode and two-electrode systems.

Main Results:

• Successfully synthesized flexible, porous LCNF co-doped with N, S, and Zn.
• Optimized L-NS20-Zn15 fibers achieved a specific capacitance of 328.6 F g^-1 (three-electrode) and 46.8 F g^-1 (supercapacitor).
• The supercapacitor demonstrated an energy density of 25.8 Wh kg^-1 at 200 W kg^-1 and 86% capacitance retention after 3000 cycles.

Conclusions:

• Co-doped LCNF exhibit significantly enhanced electrochemical performance compared to undoped counterparts.
• The developed material offers a sustainable and efficient solution for high-performance supercapacitors.
• This work highlights the potential of lignin-derived materials in next-generation energy storage devices.