A large proportion of electronic devices that are discarded at the end of their lives are never recycled, and a large part of the problem is the difficulty of isolating and recovering the valuable materials that make them. With a view to solving this problem, engineers at Duke University have developed the world’s first fully recycled printed electronics, which is displayed as a transistor with the help of baths and sound waves in their original building blocks Can be reduced.
This is the latest advance in the world of printable electronics, where conductive inks combine with common printing techniques to create thin and flexible electronic circuits, which came about through experimentation with nanocallulose. Derived from plants and often wood waste, we have seen how this common material can be used in advanced water filters, squishy batteries and environmentally friendly plastics.
We’ve also seen before how it can be used as a substrate for wood-based computer chips, although Duke University engineers set their sights slightly higher, to produce an even more environmentally Looking to leverage its potential as an insulating material. Compatible computer components.
Study author Aaron Franklin says, “Nanocellulose is biodegradable and has been used for years in applications such as packaging.” “And while people have long known about its potential applications as an insulator in electronics, no one has figured out how to use it in the first printing ink. This is one of the keys to making these fully recyclable devices functional. “
Franklin and his team have employed a way to incorporate nanocallulose into printable inks to reduce it to a crystalline form and to add a splash of salt. This insulating, dielectric ink was combined with a conductive ink made from graphene and a semiconductor ink made of carbon nanotubes, to create an all-carbon transistor that can be used at room temperature using an aerosol jet printing The paper can be printed on the substrate.
In testing, the team demonstrated its capabilities as a paper-based lactate sensor and stated that the transistor performed well enough to serve a range of uses while remaining stable over six months.
The recycling process for the transistor begins by immersing it in a series of baths, and vibrating it slowly with sound waves. A centrifuge allows carbon nanotubes and graphene to be recovered at a yield close to 100 percent to be re-used with the same printing process after resolving the result. Meanwhile, nanocellulose can be recycled with a paper substrate.
“These types of reusable electronics are not going to change and go out of the entire half-trillion-dollar industry in any way, and we’re certainly nowhere,” says Franklin. “But demonstrating these types of new materials and their functionality is expected to be a step in the right direction for the new type of electronics life cycle.”
The research was published in the journal Nature electronics.
Source: Duke University