It will someday be possible for self-healing smart coatings to make scratches on cell phones a thing of the past. However, researchers frequently have to compromise between strength and the potential to self-repair when producing these materials. One group reports in ACS Nano on the production of a smart coating that is as hard as tooth enamel on the outside but can heal itself just like skin.
The smart coating market is a flourishing industry and is only anticipated to grow in the future. The most common smart coatings that can help heal themselves are based on soft polymers that can wear out very fast. However, Ming Yang and colleagues developed a stiffer, more healable coating, but its performance will still have to be optimized. In the present paper, the researchers have come up with a different way for making a soft, yet hard, self-healing material.
Imitating the structure of human skin, the researchers employed a layer-by-layer technique to produce a dynamic, soft under layer comprising of tannic acid and polyvinyl alcohol. The hard outer layer contained these compounds including a layer of graphene oxide. When fabricated at a specific thickness, the material effectively healed itself when cut and was also capable of killing bacteria. The material could someday function as an electronic skin or even as a scratch-proof coating on phones or buildings.
The authors received funding for their work from the National Natural Science Foundation of China.