Nano material researchers from the University of Illinois at Chicago (UIC) and Korea University have invented a cheap ultra-thin film that is both transparent and highly conductive to electric current, offering promise for bendable, wearable electronic devices like smart watches. The film — a mat of tangled nanofibre — is also bendable and stretchable, offering potential applications in roll-up touchscreen displays, wearable electronics, flexible solar cells and electronic skin. Also Read - Facebook for Android will soon get dark mode and coronavirus tracking featureAlso Read - Scientists develop soft contact lens that can zoom with a blink
It is difficult to make materials that are both transparent and conductive, said Alexander Yarin, distinguished professor of mechanical engineering at UIC. The new film establishes a “world-record combination of high transparency and low electrical resistance, the latter at least 10-fold greater than the previous existing record, informed Sam Yoon, professor of mechanical engineering at Korea University. Also Read - Increasing smartphone usage may be resulting in growing horns on our skull; research suggests
The film also retains its properties after repeated cycles of severe stretching or bending — an important property for touchscreens or wearables. The manufacturing begins by electrospinning a nanofibre mat of polyacrylonitrile or PAN, whose fibres are about one-hundredth the diameter of a human hair. The fibre shoots out like a rapidly coiling noodle, which when deposited onto a surface intersects itself a million times. The fibre is then electroplated with copper or silver, nickel or gold. The electrospinning and electroplating are both relatively high-throughput, commercially viable processes that take only a few seconds each, according to the researchers.
We can then take the metal-plated fibres and transfer to any surface — the skin of the hand, a leaf, or glass,” Yarin added in a paper reported in the journal Advanced Materials. An additional application may be as a nano-textured surface that dramatically increases cooling efficiency, he noted.