(November 17, 2015) Flexible sensors have been developed for use in consumer electronics, robotics, health care, and space flight. Future possible applications could include the creation of ‘electronic skin’ and prosthetic limbs that allow wearers to ‘feel’ changes in their environments.
One problem with current flexible sensors, however, is that they can be easily scratched and otherwise damaged, potentially destroying their functionality. Researchers in the Department of Chemical Engineering at the Technion – Israel Institute of Technology in Haifa (Israel), who were inspired by the healing properties in human skin, have developed materials that can be integrated into flexible devices to “heal” incidental scratches or damaging cuts that might compromise device functionality. The advancement, using a new kind of synthetic polymer (a polymer is a large molecule composed of many repeated smaller molecules) has self-healing properties that mimic human skin, which means that e-skin “wounds” can quickly “heal” themselves in remarkably short time – less than a day.
“The vulnerability of flexible sensors used in real-world applications calls for the development of self-healing properties similar to how human skins heals,” said self-healing sensor co-developer Professor Hossam Haick. “Accordingly, we have developed a complete, self-healing device in the form of a bendable and stretchable chemiresistor where every part – no matter where the device is cut or scratched – is self-healing.”
The new sensor is comprised of a self-healing substrate, high conductivity electrodes, and molecularly modified gold nanoparticles. “The gold particles on top of the substrate and between the self-healing electrodes are able to “heal” cracks that could completely disconnect electrical connectivity,” said Prof. Haick.