High-Performance Supercapacitor Electrode Materials from Cellulose-Derived Carbon Nanofibers

Area of Science:

• Materials Science
• Electrochemistry
• Nanotechnology

Background:

• Supercapacitors are crucial for energy storage.
• Developing advanced electrode materials is key to improving supercapacitor performance.
• Nitrogen-functionalized carbon materials show promise for electrochemical applications.

Purpose of the Study:

• To synthesize nitrogen-functionalized carbon nanofibers (N-CNFs) from polypyrrole-coated cellulose.
• To evaluate N-CNFs as electrode materials for supercapacitors.
• To fabricate and test an asymmetric supercapacitor device using N-CNFs and N-CNFs/Ni(OH)2.

Main Methods:

• Electrospinning of cellulose acetate nanofibers.
• Deacetylation and subsequent polypyrrole (PPy) polymerization to create PPy-coated cellulose NFs.
• Carbonization to yield nitrogen-functionalized carbon nanofibers (N-CNFs).
• Fabrication of supercapacitor electrodes and an asymmetric device.

Main Results:

• N-CNF electrodes exhibited a specific capacitance of ~236 F g(-1).
• N-CNF/Ni(OH)2 composite electrodes showed a significantly higher specific capacitance of ~1045 F g(-1).
• The asymmetric supercapacitor achieved a working voltage of 1.6 V, energy density of ~51 Wh kg(-1), and power density of ~117 kW kg(-1).
• The device demonstrated excellent cycle stability, retaining ~84% capacitance after 5000 cycles.

Conclusions:

• N-CNFs derived from electrospun cellulose are effective electrode materials for high-performance supercapacitors.
• The N-CNFs/Ni(OH)2 composite enhances capacitance, leading to superior energy storage capabilities.
• These materials hold potential for advanced energy storage device development.