A new kind of flower power.
When you think of flowers, words that come to mind probably don’t include electricity, circuits or transistors. But a team of researchers from the Laboratory of Organic Electronics at Linköping University in Sweden managed to turn a rose into an electronic circuit by filling its veins with a conductive polymer.
Their first challenge was to find a polymer that would not be toxic for the plant. It had to be water-soluble, conduct electricity, and form wires while travelling through the rose’s vascular system. They began by removing the stem and leaves before soaking the rose in a solution of PEDOT, a classical conducting polymer used in traditional electronics. Although it took a couple of days, the polymer travelled through the plant and solidified into a gel that contained self-generated wires almost 4 inches in length. It even let the plant continue to get the nutrients and water it needed to survive.
Researchers were then able to build electrochemical transistors by combining the wires with gold electrodes. These transistors converted ionic signals to an electronic output that could be used in digital logic gate functions. They also used a different technique to flush PEDOT into the pores of the flower so that they could run a current across the leaves and make them change color.
In a press release, Linköping University speculates that “Controlling and interfacing with chemical pathways in plants could pave the way to photosynthesis-based fuel cells, sensors and growth regulators, and devices that modulate the internal functions of plants.”
Imagine being able to use plants to harvest solar energy or to use this type of circuit to improve plant growth instead of genetically modifying them. Bergen, one of the researchers on the project, said, “When we have tapped out resources from nature in the past we have always chopped it or burnt it. Maybe this could be a way of tapping energy from plants without having to kill them.”
The team’s idea of combining electronics and plants began in the 1990s when they researched putting electronics directly into trees, but their plans were cut short due to a lack of funding. Now that they have independent money from the Knut and Alice Wallenberg Foundation, they can continue their work and build plans for the future.