Experiment with using kombucha to make circuit boards

A small international team of computer and materials engineers tested the possibility of using kombucha to make electronic circuit boards. Their article, published on arXiv preprint server, describing different methods of printing circuits onto dry mats.

Kombucha is a type of tea consumed by people all over the world. It is made by adding a symbiotic culture of bacteria and yeast (SCOBY) to a container of sugar water and flavoring and letting it brew for several weeks. What’s unique is that creating a tea container leads to the creation of a second SCOBY—similar in some ways to making sourdough bread using a “starter”.

SCOBY is used to make kombucha look like a dead sea creature and has uses beyond making tea. It is a block of cellulose fibers, which makes it flexible. In the past, some people have discovered that if dried, the resulting rug can be used to make a fabric. The team has previously discovered that mats can also be used to create what they describe as live kombucha mats that conduct electricity. For the new study, they wondered if these mats could be dried and used as the backing for circuit boards in functional, wearable devices.

To test this possibility, the team purchased several samples of kombucha and used them to grow their own SCOBY mats. Each rug is then air-dried and tested in multiple ways. One of the early tests was to determine if the mats would hold together in a way that would allow them to be used as a circuit liner. The team found that they are not only durable and will, in fact, retain their shape when heated to temperatures as high as 200 degrees Celsius.

Satisfied that they’d done something, the team then tried printing the circuits onto the carpet using conductive polymers through an aerosol inkjet printer. They also tested them with a 3D printer. They found both approaches to be as effective as they expected. They discovered that they could even attach LEDs to it circuit board and they will light up. They concluded that while more testing is needed, it seems kombucha mats are a viable option for creating wearable electronics.

© 2023 Science X Network