Hierarchical microporous/mesoporous carbon nanosheets for high-performance supercapacitors

Area of Science:

• Materials Science
• Electrochemistry
• Nanotechnology

Background:

• Supercapacitors require advanced electrode materials for enhanced energy storage.
• Carbon-based materials are promising due to their tunable properties and conductivity.
• Developing cost-effective and high-performance carbon electrode synthesis is crucial.

Purpose of the Study:

• To develop a straightforward one-pot synthesis for highly porous carbon nanosheets.
• To evaluate the electrochemical performance of these nanosheets as supercapacitor electrodes.
• To investigate the structure-property relationships governing their performance.

Main Methods:

• One-pot carbonization of sodium gluconate at 700-900 °C.
• Optional additional activation step to enhance textural properties.
• Characterization of material morphology, surface area (BET), and porosity.
• Electrochemical testing in H2SO4 and TEABF4/AN electrolytes.

Main Results:

• Synthesis of carbon nanosheets with high aspect ratio and hierarchical microporous/mesoporous structure.
• Achieved BET surface areas up to 1390 m(2) g(-1), enhanced to 1890 m(2) g(-1) after activation.
• Specific capacitances of 140 F g(-1) at 150 A g(-1) (aqueous) and 100 F g(-1) at 120 A g(-1) (organic).
• High specific power (up to 110 kW kg(-1)) and excellent cycling stability.

Conclusions:

• The one-pot synthesis provides a facile route to high-performance carbon nanosheet supercapacitor electrodes.
• Hierarchical porosity and nanosheet morphology facilitate rapid ion transport, boosting electrochemical performance.
• The synthesized materials demonstrate significant potential for high-power energy storage applications.