Skin-worn flexible electronics show great promise, in applications ranging from health monitoring to gesture control. The devices could soon also be more eco-friendly, as scientists have recently developed a method of making them from fish scales.
Ordinarily, so-called "electronic skin" gadgets consist of a flexible, stretchable, transparent plastic film base, which electronic components are embedded within. They're typically not intended to be worn for more than about a week, however, after which they will simply get thrown away.
With this situation in mind, a team of scientists from China's Nanjing Tech University set out to develop a more environmentally-friendly alternative.
Led by Hai-Dong Yu, Juqing Liu and Wei Huang, they started with waste fish scales that would otherwise have been discarded. The researchers proceeded to develop a gelatine derived from the collagen in those scales, then poured that gel into a petri-dish mold and allowed it to dry into a film. When tested, that film proved to be flexible, transparent and durable enough for use in electronic skin.
Although devices made with the film wouldn't necessarily be used for longer periods of time than their conventional counterparts, they also wouldn't utilize petroleum-based plastic that would sit in landfills for years after being disposed of. In fact, if mixed with 60 ºC (140 ºF) water for a few seconds, the film dissolves back into a gelatine that can be reused. And if buried in soil, the material completely biodegrades within 24 days.
As a demonstration of the film's functionality, the team used it to construct an alternating-current electroluminescent device, which continued to glow after being bent and relaxed 1,000 times.
The research is described in a paper that was recently published in the journal ACS Nano.
Source: American Chemical Society