An Ultra-High-Energy Density Supercapacitor; Fabrication Based on Thiol-functionalized Graphene Oxide Scrolls

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Graphene-based electrodes for supercapacitors face challenges in achieving high energy density due to restacking and reduced electrical conductivity.
• Chemical modification of graphene often leads to lower conductivity and limited surface area, hindering ion accessibility and energy storage performance.

Purpose of the Study:

• To overcome the limitations of current graphene electrodes for supercapacitors.
• To develop novel electrode materials offering high energy density without compromising power density.

Main Methods:

• Synthesis of thiol-functionalized, nitrogen-doped, reduced graphene oxide scrolls.
• Fabrication of electric double-layer supercapacitors using the novel scrolls as electrode materials.

Main Results:

• The fabricated supercapacitor demonstrated high energy density (206 Wh/kg) and power density (496 W/kg) at low current density.
• Exceptional power density (32 kW/kg) and energy density (9.58 Wh/kg) were achieved at high current density.
• The supercapacitor operated over a 0-4 V voltage range with over 20,000 cycles of excellent cyclic stability.

Conclusions:

• Thiol-functionalized, nitrogen-doped reduced graphene oxide scrolls represent a promising electrode material for high-performance supercapacitors.
• This scroll-based electrode design offers a viable strategy for next-generation energy storage devices requiring high energy density.
• The combination of scroll architecture and tailored functionalization effectively addresses graphene restacking and conductivity issues.