The new study is the first to "combine" self-healing materials and ionic conductors into one. Self-healing materials automatically repair wear and tear caused by use, extending their lifespan and reducing costs, while ionic conductors, which allow ions to flow within them, play an important role in energy storage, solar energy conversion, sensors and electronic devices. Chao Wang said, "Developing materials that combine multiple superior properties has been an unsolved problem in science for many years, and now we have succeeded in doing so and have set out to develop its related applications."

  The paper's co-author, Christopher Keplinger, an associate professor at the University of Colorado at Boulder, previously developed ionic conductors that could power artificial muscles and use them to make transparent speakers, but could not heal themselves after mechanical failures. The reason for the inability to heal itself is that the covalent bonds contained within these polymers react in an electrochemical environment, reducing the material's performance. Wang Chao used the ionic dipole effect to allow coupling between charged ions and polar molecules, thus greatly improving the stability of the ionic conductor, and eventually developed a new self-healing material that combines a variety of superior properties.

  This rubber-like soft material is low-cost, easy to produce, and can be extended to 50 times its initial length. When cut, it can be reconnected (self-healing) within 24 hours at room temperature and can be extended twice again in only 5 minutes after self-healing.

  Chao Wang's team also used the new material to develop a new type of artificial muscle. The artificial muscle is made of three layers of material, the top and bottom layers are new materials that can conduct electricity and heal themselves, and the middle layer is a transparent non-conductive rubber-like film. They applied electrical signals and found that the artificial muscle could start moving like a human biceps; more importantly, when it broke into two pieces, it could recover to the same level of performance as before it was severed without relying on any external stimulation.