In a literally green technological advance, a team of researchers has found a way to replace the conventional printed circuit board (PCB) in electronic devices with a biodegradable alternative made out of tree leaves. Reported earlier this month in Science Advances, such “leaftronics” could help reduce the tens of millions of tons of electronic waste, or e-waste, humanity produces every year.
The idea is “very exciting” and “quite promising,” said Lan Yin, a materials scientist and engineer at Tsinghua University, who works on developing biodegradable electronics but was not involved in the study.
E-waste is everywhere and piling up fast. In 2022, manufacturers produced 62 million tons of e-waste globally. And that figure is expected to increase by more than 30 percent by 2030, because modern electronics are designed to be disposable, said Rakesh Nair, a postdoctoral researcher and engineer with the Institute for Applied Physics at the Dresden University of Technology (TU Dresden). “We can easily make electronics that last for 10 or 20, 30 years, but we deliberately make them so that you buy the new model,” Nair said.
By mass, circuit boards make up as much as 60 percent of e-waste. PCBs are typically made of extremely tough plastic or fiberglass infused with epoxy, an unrecyclable substrate that is “the core of the problem,” said Hans Kleemann, an experimental physicist at TU Dresden and Nair’s adviser. “It really stops you from all these important things like recycling and reusing components.” So Kleemann, Nair and colleagues set out to find a greener alternative.
Nair first thought of using paper for the boards but was dissuaded by the amount of water and pollutants needed to generate paper. One day, when looking at the large magnolia tree near his institute, “it just clicked”: He could use its leaves instead.
Biodegradable yet tough enough to withstand hurricanes, leaves get their strength from their “skeleton,” a highly ramified network of fine veins made of a woody compound called lignocellulose. To turn a magnolia leaf into circuit board material, Nair first stripped it down to its skeleton by chemically removing the leaf’s cells. He then filled in the skeleton’s holes with ethyl cellulose, a tough biodegradable polymer. The resulting flexible board withstood all sorts of electronics manufacturing processes, including cutting shapes into the boards with lasers, printing circuits on top of them with commercially used silver inks, and soldering components to them.
Nair even put a leaf in the team’s state-of-the-art physical vapor deposition machine and laid down layers of material to make organic light-emitting diodes, resulting in a light-up leaftronic. Nair said he told Kleemann about that test only after its success, because it was possible it could have damaged the expensive machine.
Not only do Nair’s leaftronics perform well, they break down well, too. The team was able to remove the expensive metals and circuit components by placing leaftronics in an ultrasonic acid bath. The boards themselves began to degrade after just one month in a compost heap.
Leaftronics also generate much lower emissions during production than regular boards, the researchers calculate. Nair ultimately envisions an electronics manufacturing and recycling plant situated next to a tree farm, so leaves could be sustainably harvested, made into leaftronics, then recycled (the circuitry) or degraded and used as fuel (the leaf). “Nothing is wasted,” he indicated.
As with any budding technology, the biggest challenge will likely be convincing electronics manufacturers to adopt leaftronics. Although the materials performed well in laboratory tests, that may not be enough to induce manufacturers to switch to them. Because of their biodegradability, leaftronics also likely won’t meet certain industry standards.
Current PCB materials are practically unbeatable in terms of robustness, and they are the benchmark for current rules regarding electronic components, Kleeman notes. “Maybe [regulators] have to lower the barrier [on stability] by 5 percent to allow us to get into this market,” he said.
Published September 2025