Optimizing Performance in Supercapacitors through Surface Decoration of Bismuth Nanosheets

Area of Science:

• Materials Science
• Electrochemistry
• Nanotechnology

Background:

• Bismuth (Bi) offers high theoretical capacity and conductivity for supercapacitors.
• Bismuth electrode materials suffer from volume expansion and pulverization, limiting capacitance.
• Nonmetal decoration can modulate material morphology and electronic structure.

Purpose of the Study:

• To investigate the effect of selenium (Se) decoration on bismuth nanosheets for supercapacitor applications.
• To enhance the electrochemical performance and stability of bismuth-based electrodes.

Main Methods:

• Fabrication of Se-decorated Bi nanosheets on nickel foam (NF) using chemical vapor deposition.
• Characterization using various techniques to analyze morphology, chemical state, and phase structure.
• Electrochemical testing of Se-decorated Bi nanosheets in supercapacitors.

Main Results:

• Se decoration regulated the surface morphology and chemical state of Bi nanosheets while maintaining their phase structure.
• Se-decorated Bi nanosheets showed a 51.1% improvement in capacity (1313 F/g) compared to pristine Bi nanosheets (869 F/g) at 5 A/g.
• An asymmetric supercapacitor assembled with Se-decorated Bi nanosheets achieved an energy density of 151.2 Wh/kg at a power density of 800 W/kg.

Conclusions:

• Se decoration is a promising strategy to enhance the capacity and electrochemical performance of Bi nanosheets.
• The developed Se-decorated Bi nanosheets show potential for advanced energy storage applications.
• Surface modification of electrode materials is crucial for overcoming limitations in supercapacitor performance.