🌱 Can circuit boards be made from leaves?
Printed circuit boards (PCBs) play a central role in close to all electronic devices. Therewith, they also contribute massively to the global production of e-waste. PCBs are traditionally made from non-recyclable materials – such as fibre glass and composite plastic. This also means that “they often end up in landfills or are incinerated to recover valuable metals”. Yet, researchers from the Dresden University of Technology in Germany have recently created a new type of biodegradable circuit board made from leaves. This technology is a type of “organic circuitry”, which is called “leaftronics”. It was notably created in an effort to reduce e-waste.
🌱 How are leaftronics produced?
To date, leaftronics have been made using a leaf from a magnolia tree. This leaf is stripped to “its stem and veins”. It is then dipped into a container filled with a polymer that is both durable and compostable, namely ethyl cellulose. This results in a “smooth, flexible and transparent material, capable of withstanding high temperatures”. This material can then be laser-cut into “leaf-based circuit boards”, printed on with circuits, and the necessary components can be soldered onto its surface.
🌱 How do leaftronics compare with other biodegradable PCBs?
In the past, several biodegradable PCBs have been made using alternative materials – such as silk, paper, and mushroom skins. Yet, in comparison to other materials, the reliance of leaftronics “on natural leaf scaffolds simplifies the production process while also enhancing the material's thermal and mechanical properties”. This notably makes leaftronics “a genuine candidate for mass production”.
🌱 Will leaftronics become the industry standard?
Leaftronics have performed well in their initial testing. They are biodegradable and unlike traditional PCBs, leaftronics “can be left in an acid bath to remove any valuable metals” before being degraded. They can “handle elevated temperatures well” and their production is “not energy intensive”. The adoption of leaftronics in the electronics industry, however, has an uncertain future. Even though many electronic devices are often discarded within a few years, durability is still largely prioritized for PCBs. It is still too early to say precisely how durable leaftronics are and how willing the electronics sector will be to embrace this new technology.
Read more about leaftronics here:
- https://sustainabilitymag.com/articles/meet-leaftronics-the-circuit-board-technology-made-of-leaves
- https://www.pflanzenforschung.de/de/pflanzenwissen/journal/leaftronics