Smartphones use millions of transistors – a mini electronic component, kind of like a computer brain cell, working to either increase an electric current or as a switch (a small current in one part can activate a larger current in another part) – and they currently can’t be recycled. However, in the US, the world’s first fully recyclable, printed electronics are being developed to tackle gadget waste.
Trying to create and dispose of transistors in an environmentally friendly way has been a tough challenge for many years.
But not anymore! Scientists at Duke University have created a fully functional transistor made out of carbon inks that can be easily 3D-printed onto paper. This will replace the unsustainable silicon chips that you’ll find in many of your gadgets, as did you know that the average computer chip does more harm to the environment than a car?! And the manufacture of the tiny, wafer-thin slivers of silicon leaves behind a mountain of waste.
Creating this recyclable transistor technology has been helped by the development of a wood-derived insulating dielectric ink called nanocellulose. Put simply, this means the ink allows an electrical current to flow through it, but only when placed in an electric field – where negative charges split from their positive counterparts, and travel to their opposing electrodes (negative goes to positive, and positive goes to negative). If there is no external electrical field acting on the ink – no current gets through, making it very safe and perfect for use in these types of devices.
Nanocellulose is biodegradable and scientists were able to extract this just by sprinkling table salt on tiny wood fibres, resulting in an ink that, when combined with other printable inks, provides a strong substitute material.
So far, the materials created in this process show no signs of letting up after six months – so it looks like they can stand the test of time. And when the new transistor does eventually pack up, it can simply be recycled due to its wooden components, along with the paper it was produced on. Pretty nifty stuff!
So, what next?
We can’t get enough of our ever-advancing technology, but it’s created an unsustainable problem of us discarding devices in favour of the latest all-singing, all-dancing models.
Last decade saw waste from electronic devices become the fastest growing stream of unmanageable disposal in the world. Imagine the impact we could have by simply producing fewer throwaway parts? The next logical step for printable recyclable electronics would be to find a way to put these components into larger computer processors – making them even more useful across a wider range of technology.
This technology could also help with the shortage of microchips (a set of electric circuits on a silicon board, containing lots of transistors) which is affecting pretty much every industry around the globe at the moment. Car production has taken a massive hit due to the lack of microchips, and even the slightest of delays can have catastrophic effects on the production of electronic products.
So, by creating fully recyclable and easily printable electronics, and showing what they can do, the electronic world can be even greener – now that’s an upgrade we’re on board with!
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