Two-Dimensional Porphyrin-Based Covalent Organic Frameworks/g-C₃N₄ Composites as High-Performance Supercapacitor

Area of Science:

• Materials Science
• Electrochemistry
• Nanotechnology

Background:

• Covalent Organic Frameworks (COFs) are promising for energy storage due to high porosity and redox activity.
• Poor electron conductivity and limited pore accessibility in COFs hinder their supercapacitor performance.
• Integrating COFs with conductive materials is a key strategy to overcome these limitations.

Purpose of the Study:

• To synthesize and evaluate novel COF-g-C3N4 composites as electrode materials for supercapacitors.
• To investigate the effect of varying COF content on the electrochemical performance of the composites.
• To demonstrate the potential of these composites for high-performance energy storage.

Main Methods:

• Fabrication of porphyrin-based COF@g-C3N4 composites via in situ solvothermal synthesis.
• Preparation of composites with different COF ratios (POR-COF@g-C3N4-X, X = 10-40%).
• Electrochemical characterization of the materials as supercapacitor electrodes.

Main Results:

• The optimized POR-COF@g-C3N4-30 composite exhibited a specific capacitance of 788 F g-1 at 4 A g-1.
• The composite demonstrated significantly higher capacitance compared to pristine COF.
• An asymmetric device using POR-COF@g-C3N4-30 achieved 24.4 Wh kg-1 energy density and 74% capacity retention after 6000 cycles.

Conclusions:

• COF-g-C3N4 composites are effective electrode materials for supercapacitors.
• The synergistic effect between COF and g-C3N4 enhances electrochemical performance.
• These materials offer a promising route towards highly efficient and stable energy storage devices.