Researchers from KAUST created durable electronic skin (e-skin) that can perform difficult tasks without breaking.
E-skin will play an important role in the next generation of prosthetics, personalized medicine, soft robotics and AI. But it is difficult to create flexible electronics for e-skins that are durable and can perform delicate tasks. Most e-skins are created by layering active nanomaterials on a stretchy surface that attaches to the human skin. But often the connection between the e-skin layers is weak, which lowers its sensitivity. On the other hand, if the connection is too strong, flexibility is limited and the material is more likely to crack.
The team’s new e-skin was made of a hydrogel reinforced with silica nanoparticles. The hydrogel layer acts as a strong and stretchy substrate. Hydrogels are over 70% water, which is comparable to human tissue. The sensing layer is made of a 2D titanium carbide MXene. The layers are bound together with a highly conductive nanowire.
The hydrogel layer was pre-stretched in all directions and then applied to a layer of nanowires. Conductive pathways were created on the sensor layer. These pathways remained intact even when the material was stretched to 28 times its original size.
The prototype e-skin can sense objects from 20 cm away and it responds to stimuli in less than a tenth of a second. After testing, the team found that the e-skin worked even after 5,000 deformations and recoveries in a quarter of a second.
The team said their e-skin could be used to monitor a range of biological information. The gathered data could be shared and stored in the cloud via Wi-Fi. They believe that one day the e-skin could be used to monitor the health of inanimate objects.