Researchers at Linköping University, together with colleagues from the KTH Royal Institute of Technology, have now developed the world’s first electrical transistor made of wood. Credit: Thor Balkhed
Key points:
- Researchers have developed the world’s first transistor made of wood.
- In tests, the transistor shows it could regular electric current and provide continuous function at a selected output level.
- The transistor is slow now, but the team says it has huge development potential.
Researchers at Linköping University and the KTH Royal Institute of Technology have developed the world’s first electrical transistor made of wood.
Transistors—invented almost 100 years ago—are a crucial component in today’s modern electronic devices.
In previous trials, transistors made of wood have been able to regulate ion transport only. And when the ions run out, the transistor stops functioning. The transistor developed by the Linköping researchers, however, can function continuously and regulate electricity flow without deteriorating.
“We’ve come up with an unprecedented principle. Yes, the wood transistor is slow and bulky, but it does work, and has huge development potential,” said Isak Engquist, senior associate professor at the Laboratory for Organic Electronics at Linköping University.
According to the paper published in PNAS, the research team used balsa wood to create their transistor, as the technology involved requires a grain-less wood that is evenly structured throughout. They removed the lignin, leaving only long cellulose fibers with channels where the lignin had been. These channels were then filled with a polymer, called PEDOT:PSS, resulting in an electrically conductive wood material.
In tests, the transistor showed it could regulate electric current and provide continuous function at a selected output level. It could also switch the power on and off, albeit with a delay.
Possible applications include regulating electronic plants. One advantage of the transistor channel being so large is that it could potentially tolerate a higher current than regular organic transistors, which could be important for certain future applications.
“We didn’t create the wood transistor with any specific application in mind. We did it because we could. This is basic research, showing that it’s possible, and we hope it will inspire further research that can lead to applications in the future,” said Engquist.