Glowing LED trees to replace street lamps

Researchers from the Academia Sinica and the National Cheng Kung University in Taipei and Tainan have implanted glowing, sea urchin-shaped gold nanoparticles, known as bio light emitting diodes, or bio LEDs, inside the leaves of a plant. The new nanoparticles could replace the electricity powered street light with biologically  powered light that removes CO2 from the atmosphere 24 hours a days.

“In the future, bio-LED could be used to make roadside trees luminescent at night. This will save energy and absorb CO2 as the bio-LED luminescence will cause the chloroplast to conduct photosynthesis,” Discovery News quoted Yen-Hsun Su in an interview with Chemistry World as saying. The gold, sea urchin-shaped nanoparticles are the key to turning a material that normal absorbs light into one that emits it.

Chlorophyll, the photosynthetic pigment that gives leaves their characteristic green colour, is widely known for its ability to absorb certain wavelengths of light.

However, under certain circumstances, such as being exposed to violet light, chlorophyll can produce a light of its own. When exposed to light with a wavelengths of about 400 nanometres the normally green coloured chlorophyll glows red.

Violet light is hard to come by though, especially at night, when glowing leaves would be useful to drivers and pedestrians. The scientists needed a source of violet light, and found it in the gold nanoparticles.