Crumpled MXene Electrodes for Ultrastretchable and High-Area-Capacitance Supercapacitors.

Area of Science:

• Materials Science
• Electrochemistry
• Nanotechnology

Background:

• Two-dimensional transition metal carbides (MXenes) possess excellent electrical properties but limited flexibility.
• High stiffness of MXenes hinders their use in stretchable and wearable energy storage devices.
• Existing methods to improve deformability often compromise specific capacitance.

Purpose of the Study:

• To develop ultrastretchable and high-performing supercapacitors using MXene electrodes.
• To overcome the stiffness limitations of MXenes for flexible electronics.
• To achieve high specific capacitance and mechanical stability in stretchable supercapacitors.

Main Methods:

• Fabrication of crumpled MXene films with optimized thickness (∼3 μm).
• Characterization of mechanical strain tolerance and electrochemical performance.
• Assembly and testing of symmetric supercapacitors using crumpled MXene electrodes.

Main Results:

• Identified ∼3 μm crumpled MXene films as optimal for mitigating crack formation under strain.
• Achieved a high specific capacitance of ∼470 mF cm^-2.
• Demonstrated ultrahigh stretchability up to 800% area strain with >90% capacitance retention after 1000 cycles.

Conclusions:

• Crumpled MXene textures provide an effective strategy for creating ultrastretchable electrodes.
• This approach enables high-performance supercapacitors suitable for wearable electronics.
• Offers a pathway for designing stretchable electrodes from various 2D nanomaterials.