Dimethylsulfoxide-Dependent Environments for Fabricating Graphene Hydrogels for High-Performance Supercapacitor

Area of Science:

• Materials Science
• Electrochemistry
• Nanotechnology

Background:

• Graphene oxide (GO) is a precursor to reduced graphene oxide (RGO).
• Developing 3D porous RGO structures is crucial for advanced energy storage applications.

Purpose of the Study:

• To synthesize reduced graphene oxide hydrogels (DRGHs) with 3D porous structures.
• To investigate the electrochemical performance of DRGHs as supercapacitor electrodes.
• To explore the effect of reductant dosage on material properties and performance.

Main Methods:

• Chemical reduction of graphene oxide using dimethylsulfoxide (DMSO) in an alkaline ammonia environment.
• Characterization using X-ray powder diffraction (XRD), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FT-IR), field emission scanning electron microscopy (FESEM), and high-resolution transmission electron microscopy (HRTEM).
• Electrochemical testing of supercapacitors fabricated with DRGHs electrodes.

Main Results:

• Successful synthesis of 3D porous DRGHs with interconnected graphene sheets confirmed by microscopy and spectroscopy.
• DRGHs exhibited enhanced electrochemical performance with increasing DMSO dosage.
• Specific capacitances of 313.6, 323.6, and 348.0 F g⁻¹ were achieved at 0.2 A g⁻¹ for different DRGHs samples.
• The electrodes demonstrated good stability and reversibility during charge/discharge cycling.

Conclusions:

• The 3D porous structure of DRGHs, achieved via DMSO reduction, is beneficial for supercapacitor applications.
• Optimizing reductant dosage is key to enhancing the capacitive performance of DRGHs.
• The synthesized DRGHs show significant potential as high-performance electrode materials for supercapacitors.