‘Glow in The Dark’ refillable plants are the green light we’ve been waiting for

Scientists are working on a rechargeable, phosphorescent plant life that may one day replace some of the inefficient, energy-consuming electric lights we currently rely on for modern living.

The technology works through embedded nanoparticles that are found near the surface of the leaves. A charge of an LED light lasting 10 seconds is enough for the plant to glow for several minutes, and the nanoparticles can then be recharged repeatedly.

The research is part of a young but growing field called plant nanobionics: using nanoparticles to add additional functions and abilities to living plants. This is the second generation of the technology to be developed.

“We wanted to create an electroluminescent plant with particles that will absorb light, store some of it and gradually emit it,” explains chemical engineer Michael Strano of MIT. “It’s a big step towards herbal lighting. “

(Strano et al., Science Advances, 2021)

At the heart of glowing plants are capacitors that can store light as photons and then release them over time. A compound called strontium aluminate was used as phosphorus – a material capable of absorbing visible and ultraviolet light and emitting it as a glow.

Strontium aluminate can be made into nanoparticles, and the microscopic dots have then been coated with silica to protect them from damage. They were then embedded in the stomata of the plants – the small pores on the surface of the leaves that allow gases to pass into or out of the plant’s tissues – accumulating as a thin film inside the spongy tissue layer of the mesophyll.

The team succeeded in making the technology work effectively on five different plant species, covering a variety of leaf sizes: basil, watercress, tobacco, daisy, and Thai elephant ear.

“We need an intense light, delivered as a pulse for a few seconds, and which can charge it,” explains MIT nanoscientist Pavlo Gordiichuk.

“We have also shown that we can use large lenses, like a Fresnel lens, to transfer our amplified light over a distance of over a meter. This is a good step towards creating scale illumination. that people could use. “

An illuminated Thai elephant ear on the left. (Strano et al., Science Advances, 2021)

Further analysis revealed that the plants still photosynthesize normally and can continue to evaporate water through their stomata. After the experiments, the scientists were able to extract and reuse about 60 percent of the phosphors that had been used.

What makes the technology even more promising is that it is a significant improvement over the first generation nanoparticles used to make light plants, which used the enzymes luciferase and luciferin (as found in fireflies) to produce a very faint glow.

Later, the researchers claim that different types of nanoparticles could be combined on the same plant.

We are still a long way from this technology which can be used in practice – the shelf life of individual sheets for refill appears to be around two weeks. But it is without a doubt a bright innovation to keep an eye on the future, which could one day literally change the way we look at things.

“Creating ambient light with the renewable chemical energy of living plants is a bold idea,” says Sheila Kennedy, an architectural researcher at MIT.

“This represents a fundamental change in the way we think about living plants and electrical energy for lighting.”

The research was published in Scientists progress.