Vanadate-based Fe-MOFs as promising negative electrode for hybrid supercapacitor device

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Supercapacitor negative electrodes predominantly use carbon-based materials.
• Metal-organic frameworks (MOFs) are underexplored as negative electrode materials for supercapacitors.

Purpose of the Study:

• To synthesize and characterize novel composite materials based on graphene oxide (GO) and vanadate-based Fe-organic frameworks (Fe-VO4-BIPY).
• To investigate the effect of polyoxometalate-based metal-organic frameworks (POMOFs) deposition on graphene for improved supercapacitor performance.

Main Methods:

• Hydrothermal synthesis of GO/Fe-VO4-BIPY composite materials.
• Tuning POMOFs content to control deposition and dispersion on graphene.
• Electrochemical characterization of supercapacitor performance.

Main Results:

• The GO/Fe-VO4-BIPY-1 composite exhibited a specific capacitance of 190 F g⁻¹ at 0.5 A g⁻¹, attributed to synergistic Faraday reactions and electric double-layer capacitance.
• The composite demonstrated superior surface area and redox reaction sites compared to pristine Fe-VO4-BIPY.
• An assembled supercapacitor achieved a maximum energy density of 46.84 Wh kg⁻¹ at 850 W kg⁻¹.

Conclusions:

• The developed GO/Fe-VO4-BIPY composites offer enhanced electrochemical performance for supercapacitor applications.
• The synergistic effect between GO and POMOFs is crucial for improving charge storage capabilities.
• These materials represent a promising alternative to traditional carbon-based negative electrodes.