Just like a jellyfish, the electronic skin is transparent, stretchable, touch-sensitive, and self-healing in aquatic environments, and could be used in everything from water-resistant touchscreens to aquatic soft robots.
"One of the challenges with many self-healing materials today is that they are not transparent and they do not work efficiently when wet," said Assistant Professor Benjamin Tee, NUS. "These drawbacks make them less useful for electronic applications such as touchscreens which often need to be used in wet weather conditions."
Inspired by jellyfish, which are transparent and able to sense in wet environments, the team created a gel consisting of a fluorocarbon-based polymer with a fluorine-rich ionic liquid. When combined, the polymer network interacts with the ionic liquid via highly reversible ion-dipole interactions, which allows it to self-heal.
Elaborating on the advantages of this configuration, Asst Prof Tee explained, "Most conductive polymer gels such as hydrogels would swell when submerged in water or dry out over time in air. What makes our material different is that it can retain its shape in both wet and dry surroundings. It works well in sea water and even in acidic or alkaline environments."
The electronic skin is created by printing the material into electronic circuits. Its electrical properties change when being touched, pressed or strained. "We can then measure this change, and convert it into readable electrical signals to create a vast array of different sensor applications," Asst Prof Tee added.
The team believes the 3D printability of the materials shows potential in creating fully transparent circuit boards that could be used in robotic applications.
"We hope that this material can be used to develop various applications in emerging types of soft robots," explained Asst Prof Tee.
The electronic skin also has the potential to reduce waste. "Millions of tonnes of electronic waste from broken mobile phones, tablets, etc. are generated globally every year," he said. "We are hoping to create a future where electronic devices made from intelligent materials can perform self-repair functions to reduce the amount of electronic waste in the world."
