Cyborg plants: roots can store energy

Researchers of the HyPhOE European Project have developed biohybrid plants with an electronic root system, which could be used to store energy or as electronic sensors. This study proved the integration of circuits and electrochemical devices into the plants without damaging them, so that they continued to grow and adapt to their new hybrid state. Experiments at the NCD-SWEET beamline of the ALBA Synchrotron were crucial to shed light on the plant-based technology field.

Plants are amazing machines: not only they are solar-powered and convert carbon dioxide into chemical energy, but they are also capable of producing cellulose, the most abundant biopolymer on Earth, and can self-repair via tissue regeneration. All these factors make plants the perfect candidates for developing biohybrid technological systems, integrating smart materials and devices into their structure.

In a recent publication, the team led by researcher Eleni Stavrinidou from the Link√∂ping University (Sweden) has presented a study about biohybrid plants with an electronic root system. They found out how to integrate circuits and electrochemical devices into the plants without damaging them, so that they can continue to grow and develop, and use them as supercapacitors or electronic sensors.

The results pave the way for using roots for energy storage and the creation of a root-based supercapacitor. Supercapacitors based on conductive polymers and cellulose offer an environmentally friendly alternative for energy storage that may also be more affordable than those currently in use. As a proof of concept, the research team built a supercapacitor where the roots served as the charge storage electrodes.

Another possible application of these plant-based systems are electronic sensors. For example, by adding a humidity sensor in the root, the information could be transmitted through the electronic root network to an intelligent system, which could act accordingly by increasing or decreasing the frequency of irrigation. These discoveries open the door to new intelligent stimulus-response applications.

This study is part of the European project Hybrid Electronics Based on Photosynthetic Organisms (HyPhOE), which involves several European institutions and aims to achieve a symbiosis between photosynthetic organisms and technology.

Read more on the ALBA website

Image: Bean plant before, during and after functionalization