Mixed-valent MnSiO₃/C nanocomposite for high-performance asymmetric supercapacitor

Area of Science:

• Materials Science
• Electrochemistry
• Nanotechnology

Background:

• Supercapacitors are crucial for energy storage.
• Developing materials with high stability and energy density is essential for advanced supercapacitors.

Purpose of the Study:

• To fabricate a cost-effective carbon-coated manganese silicate (MnSiO3/C) nanocomposite.
• To investigate the electrochemical properties and supercapacitor performance of the MnSiO3/C composite.

Main Methods:

• Fabrication of MnSiO3/C nanocomposite via carbon coating and CO2 heat treatment.
• Characterization of the material's structure and morphology.
• Assembly and testing of an asymmetric supercapacitor using MnSiO3/C and activated carbon.

Main Results:

• The MnSiO3/C composite exhibited a hierarchically-porous structure with an ultrathin ordered carbon coating.
• The material displayed capacitive energy storage behavior with a stable working voltage.
• The asymmetric supercapacitor achieved 95.5% capacity retention after 10,000 cycles.
• The device delivered an energy density of 25.8 Wh/kg at a power density of 1 kW/kg with high mass loading.

Conclusions:

• The developed MnSiO3/C nanocomposite offers excellent cycling stability and energy storage performance.
• The cost-effective fabrication process and promising device performance suggest significant potential for practical supercapacitor applications.