Laminating Layered Structures of 2D MXene and Graphene Oxide for High-Performance All-Solid-State Supercapacitors

Area of Science:

• Materials Science
• Electrochemistry
• Nanotechnology

Background:

• All-solid-state supercapacitors (SCs) are crucial for flexible electronics.
• Graphene oxide (GO)-based SCs face challenges with capacitance and fabrication complexity.
• Existing SCs often rely on liquid or gel electrolytes, limiting applications.

Purpose of the Study:

• To develop a simple fabrication method for all-solid-state SCs using GO and MXene.
• To enhance the capacitance and ion transport kinetics of GO-based SCs.
• To explore the application of these SCs in humidity sensing.

Main Methods:

• Fabrication of all-solid-state supercapacitors utilizing layered graphene oxide (GO) as the solid electrolyte and MXene as electrodes.
• Characterization of the electrochemical performance, including energy storage capacitance.
• Investigation of ion transport mechanisms and the role of synergistic water absorption.
• Demonstration of the supercapacitor's application in fast-responsive humidity sensing.

Main Results:

• The fabricated all-solid-state SCs exhibit excellent energy storage capacitance, comparable to MXene-based SCs with liquid electrolytes.
• A synergistic water-absorbing effect, due to the hydrophilicity of MXene and GO, enhances interlayer spacing and ion transport.
• The SCs demonstrate fast responsiveness when applied in humidity sensing.
• The findings highlight the potential of GO as a solid electrolyte with MXene electrodes for improved capacitance.

Conclusions:

• A simple and effective method for fabricating high-performance all-solid-state supercapacitors using GO and MXene has been demonstrated.
• The synergistic hydrophilic interaction between GO and MXene significantly boosts capacitance and ion kinetics.
• These novel SCs show promise for energy storage and as electronic elements in smart devices, including humidity sensors.