Researchers develop process to produce e-skin in minutes

Researchers from the University of Illinois at Chicago and Korea University have developed a process that allows them to produce an e-skin in just a few minutes using a commercially viable process.

The ultra-thin film is transparent and highly conductive and is described as a ''self-junction copper nano-chicken wire.'' The e-skin material is a tangled nanofibre mat of polyacrylonitrile (PAN), whose fibres are very thin, and measure about one-hundredth the diameter of a strand of human hair. ''The fiber shoots out like a rapidly coiling noodle, which when deposited onto a surface intersects itself a million times,'' said UIC professor and study co-author Alexander Yarin in a prepared statement.

The electrospinning process creates a fibrous material that is very lightweight and transparent and is also flexible and durable. The film also retains the properties even after repeated bending and stretching, which makes it very suitable for wearables, roll-up touchscreen displays, and more.

After the PAN fibres are spun, in the next phase of manufacturing, the otherwise electrically inert fibres are made conductive. The fibre is first spatter-coated with metal that would attract metal ions, and it is then electroplated with copper (or silver, nickel, or gold).

"It's important, but difficult, to make materials that are both transparent and conductive," says Alexander Yarin, one of the corresponding authors of the publication, ANI reported.

According to Sam Yoon, who is also a corresponding author and a professor of mechanical engineering at Korea University, the new film had established a "world-record combination of high transparency and low electrical resistance," the latter at least 10-fold greater than the previous existing record.

According to the researchers, the electrospinning and electroplating were both relatively high-throughput, commercially viable processes that took only a few seconds each.

The study was published in the journal Advanced Materials.