Interfacial defect modulation in hydrothermal CeO₂/graphene nanocomposites for next-generation supercapacitors

Area of Science:

• Materials Science
• Electrochemistry
• Nanotechnology

Background:

• Supercapacitors are crucial for energy storage, demanding advanced materials for improved performance.
• Cerium oxide (CeO₂) and graphene are individually explored for energy applications, but their synergistic combination is less understood.

Purpose of the Study:

• To synthesize and characterize CeO₂/graphene nanocomposites using hydrothermal methods.
• To evaluate the supercapacitor performance of these nanocomposites.

Main Methods:

• Hydrothermal synthesis of CeO₂/graphene nanocomposites.
• Characterization using X-Ray Diffraction (XRD), Transmission Electron Microscopy (TEM), Raman spectroscopy, and UV-visible spectroscopy.
• Electrochemical performance evaluation via Cyclic Voltammetry (CV), Galvanostatic Charge-Discharge (GCD), and Electrochemical Impedance Spectroscopy (EIS).

Main Results:

• XRD and TEM confirmed the successful synthesis and nanoscale integration of CeO₂ within the graphene matrix.
• Raman spectroscopy validated defect-rich graphene and CeO₂ presence.
• CeO₂/Graphene nanocomposites demonstrated higher specific capacitance (231 F g^-1) compared to pure CeO₂ (142 F g^-1), improved cycling stability, and reduced charge transfer resistance, leading to enhanced energy (5.7 Wh kg^-1) and power density.

Conclusions:

• The CeO₂/graphene nanocomposite exhibits superior electrochemical performance for supercapacitor applications.
• The synergistic interaction at the CeO₂-graphene interface significantly enhances charge storage capabilities.
• These nanocomposites represent a promising avenue for next-generation energy storage devices.