Researchers at the Technical University of Denmark (DTU) have developed a new electronic material that behaves very similarly to human skin and could be used in soft robotics, medicine, and health care.
Conceptual illustration of the various applications of the material. Image from: Advanced Science
The new material is flexible, tough and self-healing and so it overcomes the known weaknesses of the rigid, brittle electronic materials currently used, which can't repair themselves. The DTU team combined the exceptional properties of graphene with the see-through polymer PEDOT: PSS, that is also electrically conductive and is, for example, used in flexible electronics and sometimes in transparent electrodes in solar cells. When the two are combined, they turn what's usually a weak, jellylike material into a solid, flexible, self-healing electronic material.
"The devices that exist today and have self-healing, soft, and responsive properties often fail to seamlessly integrate all these attributes into a single, scalable, and cohesive platform. And that is what I believe we have accomplished," says Alireza Dolatshahi-Pirouz, associate professor at DTU Health Tech and lead author of the recent paper. "Our skin-inspired material is multifunctional, endowed with the desired tactile properties, specifically designed for the usage of electronic devices. This may open doors to more advanced and versatile technologies that could more closely mingle with the human body and the surroundings."
Among the most promising attributes of the new material is its ability to self-heal. If it is damaged, it can heal in a matter of seconds, the way the human skin heals after, say, a cut. On top of that, the material is extremely malleable and can be stretched up to six times beyond its original length and still bounce back. This makes it well-suited for integration within wearable and soft robotic devices, which require that materials can be moved and bent without diminishing their performance.
It can also control heat and detect a range of environmental factors, such as pressure, temperature and pH levels, which could make it beneficial for health monitoring systems that must keep track of vital signs and adjust to body changes.
Electronics built from this material could therefore be amorphous and shape-changing, capable of adapting to their environment, the researchers say, and able to recover from damage the way biological systems do.
"The fact that the material can self-heal, regulate heat, and monitor vital signs makes it suitable to be used in a large range of equipment, says Dolatshahi-Pirouz.
"Space suits spring to mind, but I believe that we will find the most relevant uses for the individual citizen within health care. We could, for instance, incorporate it in bandages that would monitor how a wound is healing, or in devices that continuously track heart rate and temperature. The stretchable nature of the material makes it ideal for minimally invasive surgery or implantable applications. And we could easily imagine prosthetics that are more comfortable to wear and have better performance."
At present, the researchers are continuing their work and investigating methods to make it on a larger scale, aimed at eventual incorporation into real-world applications.
