Electrical engineers have enlisted the help of the humble jellyfish in their efforts to develop better light-emitting diodes (LEDs), according to a report published in the December 1 issue of the journal Advanced Materials. The Pacific Ocean jellyfish Aequorea victoria, it appears, produces just the sort of light that researchers try to coax from crystalline semiconductors such as gallium arsenide or indium phosphide. Moreover, the jellyfish accomplishes this with great efficiency: its light comesfrom a substance dubbed green fluorescent protien (GFP), which collects the energy produced in a certain cellular chemical reaction and emits it as green light from a molecular package known as a chromophore.
Inspired by Aequoreas green glow, Mark Thompson of the University of Southern California and his colleagues synthesized chromophore-like molecules, which they then seeded onto a matrix of organic molecules in an organic LED (OLED). The chromophore-like molecules, they reasoned, would function as "dopants," converting energy captured from the matrix into light. After tweaking the molecular structures a bit the team produced green and orange OLEDs.
Researchers are keen to develop such OLEDs because they would be simpler and cheaper to make than their non-organic counterparts. Although not so efficient as existing devices, further work should improve the chromophore-based model. "There are an enormous variety of fluorescent organisms," the team writes. "Other materials can be prepared using the insight provided by naturally occuring systems, which may be useful in electronic and optoelectronic applications."
