Ultrasensitive and ultrastretchable electrically self-healing conductors

Area of Science:

• Materials Science
• Nanotechnology
• Electrical Engineering

Background:

• Self-healing materials offer a bioinspired strategy to repair damaged conductors, extending electronic device lifespan.
• Current self-healing processes often require external triggers, posing challenges for practical applications.
• Developing intrinsically self-healing conductors is crucial for advancing flexible and stretchable electronics.

Purpose of the Study:

• To introduce a compliant conductor with intrinsic electrical self-healing capabilities.
• To achieve ultrahigh sensitivity to minor damages and reliable recovery from extreme deformations.
• To demonstrate practical applications in flexible and stretchable electronic devices.

Main Methods:

• Fabrication of conductive features using a scalable, low-cost process with a copper layer on liquid metal microcapsules.
• Utilizing strong interfacial interactions to trigger microcapsule rupture upon structural damage under stress.
• Investigating the self-healing mechanism's response to various degradation types, including microcracks and fractures.

Main Results:

• Achieved a compliant conductor with high conductivity (∼12,000 S/cm) and ultrahigh stretchability (up to 1,200% strain).
• Demonstrated an ultralow healing activation threshold and instantaneous electrical recovery in microseconds.
• Showcased exceptional electromechanical durability and successful implementation in an LED matrix display and electronic patch.

Conclusions:

• The developed electrically self-healing conductor exhibits remarkable performance characteristics for flexible and stretchable electronics.
• The bioinspired healing mechanism, triggered by structural damage, enables rapid and reliable conductivity restoration.
• This approach presents a promising strategy for enhancing the self-healing capabilities of compliant conductors in next-generation electronics.