A first-of-its-kind self-healing gel that is claimed to repair and connect electronic circuits has been developed by researchers in the Cockrell School of Engineering at The University of Texas. This material could create opportunities to advance the development of flexible electronics, biosensors and batteries as energy storage devices.
Technology is moving toward lighter, flexible, foldable and rollable electronics, but the existing circuits that power them are not built to flex freely and repeatedly self-repair cracks or breaks that can happen from normal wear and tear.
Until now, self-healing materials have relied on application of external stimuli such as light or heat to activate repair. The UT Austin material is said to exhibit high conductivity and strong mechanical and electrical self-healing properties.
Guihua Yu, the mechanical engineering assistant professor who developed the gel, said: "In the last decade, the self-healing concept has been popularised by people working on different applications, but this is the first time it has been done without external stimuli."
Yu and his team created the self-healing gel by combining a self-assembling metal-ligand gel that provides self-healing properties and a polymer hydrogel that acts as a conductor.
Using terpyridine molecules to create the framework and zinc atoms as a structural glue, the molecules form structures that are able to self-assemble, giving it the ability to automatically heal after a break.
When the supramolecular gel is introduced into the polymer hydrogel, forming the hybrid gel, its mechanical strength and elasticity are enhanced.
The researchers used a disc-shaped liquid crystal molecule to enhance the conductivity, biocompatibility and permeability of their polymer hydrogel. They were able to achieve about 10 times the conductivity of other polymer hydrogels used in bioelectronics and conventional rechargeable batteries.
Yu believes the self-healing gel would not replace the typical metal conductors that transport electricity, but it could be used as a soft joint, joining other parts of the circuit.
"This gel can be applied at the circuit's junction points because that's often where you see the breakage," he said. "One day, you could glue or paste the gel to these junctions so that the circuits could be more robust and harder to break."
Yu's team is also looking into other applications, including medical applications and energy storage, where it holds the potential to be used within batteries to better store electrical charge.
Author
Tom Austin-Morgan
Source: www.newelectronics.co.uk