In December of 2017, researchers at MIT announced they had found a way to create light-emitting plants. They achieved this by embedding specialized nanoparticles into the leaves of watercress plants that allowed them to give off a very dim light for nearly four hours.
At the time, they hoped that with further optimization, these plants could one day be bright enough to illuminate a home or office workspace. That day has come.
MIT engineers have now upgraded their light-emitting plants to be able to be charged by a LED in just 10 seconds, glow 10 times brighter than their first generation of plants, and last for several minutes — they can even be recharged repeatedly.
“We wanted to create a light-emitting plant with particles that will absorb light, store some of it, and emit it gradually,” said Michael Strano, the Carbon P. Dubbs Professor of Chemical Engineering at MIT and the senior author of the new study in a statement. “This is a big step toward plant-based lighting.”
The specialized nanoparticles can also boost the light production of any other type of light-emitting plant. They also contain the aptly-named enzyme luciferase, a substance found in fireflies. This process is an example of the emerging field of “plant nanobionics,” wherein researchers develop ways to augment plants with novel features.
In order to make their plants glow longer, Strano and his team created and used a "light capacitor," which is normally the part of an electrical circuit that can store photons and release them when needed.
This “light capacitor” approach could work in many different plant species, including the Thailand elephant ear, whose leaves can be more than a foot wide. The researchers have hope such glowing plants could one day be used as an outdoor lighting source.
The researchers also did further studies to evaluate whether the silica-coated nanoparticles interfered with normal plant function. They found that the glowing plants were able to photosynthesize normally without any interference.
Strano and his team are working to engineer plants that produce even brighter light for longer periods of time.